Merge trunk version 210928 into gupc branch.
[official-gcc.git] / gcc / varasm.c
blob963d8d27c1de389f541b1f8ab893b55b719ccfdf
1 /* Output variables, constants and external declarations, for GNU compiler.
2 Copyright (C) 1987-2014 Free Software Foundation, Inc.
4 This file is part of GCC.
6 GCC is free software; you can redistribute it and/or modify it under
7 the terms of the GNU General Public License as published by the Free
8 Software Foundation; either version 3, or (at your option) any later
9 version.
11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 for more details.
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING3. If not see
18 <http://www.gnu.org/licenses/>. */
21 /* This file handles generation of all the assembler code
22 *except* the instructions of a function.
23 This includes declarations of variables and their initial values.
25 We also output the assembler code for constants stored in memory
26 and are responsible for combining constants with the same value. */
28 #include "config.h"
29 #include "system.h"
30 #include "coretypes.h"
31 #include "tm.h"
32 #include "rtl.h"
33 #include "tree.h"
34 #include "stor-layout.h"
35 #include "stringpool.h"
36 #include "gcc-symtab.h"
37 #include "varasm.h"
38 #include "flags.h"
39 #include "function.h"
40 #include "expr.h"
41 #include "hard-reg-set.h"
42 #include "regs.h"
43 #include "output.h"
44 #include "diagnostic-core.h"
45 #include "hashtab.h"
46 #include "ggc.h"
47 #include "langhooks.h"
48 #include "tm_p.h"
49 #include "debug.h"
50 #include "target.h"
51 #include "common/common-target.h"
52 #include "targhooks.h"
53 #include "cgraph.h"
54 #include "pointer-set.h"
55 #include "asan.h"
56 #include "basic-block.h"
58 #ifdef XCOFF_DEBUGGING_INFO
59 #include "xcoffout.h" /* Needed for external data
60 declarations for e.g. AIX 4.x. */
61 #endif
63 /* The (assembler) name of the first globally-visible object output. */
64 extern GTY(()) const char *first_global_object_name;
65 extern GTY(()) const char *weak_global_object_name;
67 const char *first_global_object_name;
68 const char *weak_global_object_name;
70 struct addr_const;
71 struct constant_descriptor_rtx;
72 struct rtx_constant_pool;
74 #define n_deferred_constants (crtl->varasm.deferred_constants)
76 /* Number for making the label on the next
77 constant that is stored in memory. */
79 static GTY(()) int const_labelno;
81 /* Carry information from ASM_DECLARE_OBJECT_NAME
82 to ASM_FINISH_DECLARE_OBJECT. */
84 int size_directive_output;
86 /* The last decl for which assemble_variable was called,
87 if it did ASM_DECLARE_OBJECT_NAME.
88 If the last call to assemble_variable didn't do that,
89 this holds 0. */
91 tree last_assemble_variable_decl;
93 /* The following global variable indicates if the first basic block
94 in a function belongs to the cold partition or not. */
96 bool first_function_block_is_cold;
98 /* We give all constants their own alias set. Perhaps redundant with
99 MEM_READONLY_P, but pre-dates it. */
101 static alias_set_type const_alias_set;
103 /* Whether we saw any functions with no_split_stack. */
105 static bool saw_no_split_stack;
107 static const char *strip_reg_name (const char *);
108 static int contains_pointers_p (tree);
109 #ifdef ASM_OUTPUT_EXTERNAL
110 static bool incorporeal_function_p (tree);
111 #endif
112 static void decode_addr_const (tree, struct addr_const *);
113 static hashval_t const_desc_hash (const void *);
114 static int const_desc_eq (const void *, const void *);
115 static hashval_t const_hash_1 (const tree);
116 static int compare_constant (const tree, const tree);
117 static tree copy_constant (tree);
118 static void output_constant_def_contents (rtx);
119 static void output_addressed_constants (tree);
120 static unsigned HOST_WIDE_INT output_constant (tree, unsigned HOST_WIDE_INT,
121 unsigned int);
122 static void globalize_decl (tree);
123 static bool decl_readonly_section_1 (enum section_category);
124 #ifdef BSS_SECTION_ASM_OP
125 #ifdef ASM_OUTPUT_ALIGNED_BSS
126 static void asm_output_aligned_bss (FILE *, tree, const char *,
127 unsigned HOST_WIDE_INT, int)
128 ATTRIBUTE_UNUSED;
129 #endif
130 #endif /* BSS_SECTION_ASM_OP */
131 static void mark_weak (tree);
132 static void output_constant_pool (const char *, tree);
134 /* Well-known sections, each one associated with some sort of *_ASM_OP. */
135 section *text_section;
136 section *data_section;
137 section *readonly_data_section;
138 section *sdata_section;
139 section *ctors_section;
140 section *dtors_section;
141 section *bss_section;
142 section *sbss_section;
144 /* Various forms of common section. All are guaranteed to be nonnull. */
145 section *tls_comm_section;
146 section *comm_section;
147 section *lcomm_section;
149 /* A SECTION_NOSWITCH section used for declaring global BSS variables.
150 May be null. */
151 section *bss_noswitch_section;
153 /* The section that holds the main exception table, when known. The section
154 is set either by the target's init_sections hook or by the first call to
155 switch_to_exception_section. */
156 section *exception_section;
158 /* The section that holds the DWARF2 frame unwind information, when known.
159 The section is set either by the target's init_sections hook or by the
160 first call to switch_to_eh_frame_section. */
161 section *eh_frame_section;
163 /* asm_out_file's current section. This is NULL if no section has yet
164 been selected or if we lose track of what the current section is. */
165 section *in_section;
167 /* True if code for the current function is currently being directed
168 at the cold section. */
169 bool in_cold_section_p;
171 /* A linked list of all the unnamed sections. */
172 static GTY(()) section *unnamed_sections;
174 /* Return a nonzero value if DECL has a section attribute. */
175 #define IN_NAMED_SECTION(DECL) \
176 ((TREE_CODE (DECL) == FUNCTION_DECL || TREE_CODE (DECL) == VAR_DECL) \
177 && DECL_SECTION_NAME (DECL) != NULL_TREE)
179 /* Hash table of named sections. */
180 static GTY((param_is (section))) htab_t section_htab;
182 /* A table of object_blocks, indexed by section. */
183 static GTY((param_is (struct object_block))) htab_t object_block_htab;
185 /* The next number to use for internal anchor labels. */
186 static GTY(()) int anchor_labelno;
188 /* A pool of constants that can be shared between functions. */
189 static GTY(()) struct rtx_constant_pool *shared_constant_pool;
191 /* Helper routines for maintaining section_htab. */
193 static int
194 section_entry_eq (const void *p1, const void *p2)
196 const section *old = (const section *) p1;
197 const char *new_name = (const char *) p2;
199 return strcmp (old->named.name, new_name) == 0;
202 static hashval_t
203 section_entry_hash (const void *p)
205 const section *old = (const section *) p;
206 return htab_hash_string (old->named.name);
209 /* Return a hash value for section SECT. */
211 static hashval_t
212 hash_section (section *sect)
214 if (sect->common.flags & SECTION_NAMED)
215 return htab_hash_string (sect->named.name);
216 return sect->common.flags;
219 /* Helper routines for maintaining object_block_htab. */
221 static int
222 object_block_entry_eq (const void *p1, const void *p2)
224 const struct object_block *old = (const struct object_block *) p1;
225 const section *new_section = (const section *) p2;
227 return old->sect == new_section;
230 static hashval_t
231 object_block_entry_hash (const void *p)
233 const struct object_block *old = (const struct object_block *) p;
234 return hash_section (old->sect);
237 /* Return a new unnamed section with the given fields. */
239 section *
240 get_unnamed_section (unsigned int flags, void (*callback) (const void *),
241 const void *data)
243 section *sect;
245 sect = ggc_alloc<section> ();
246 sect->unnamed.common.flags = flags | SECTION_UNNAMED;
247 sect->unnamed.callback = callback;
248 sect->unnamed.data = data;
249 sect->unnamed.next = unnamed_sections;
251 unnamed_sections = sect;
252 return sect;
255 /* Return a SECTION_NOSWITCH section with the given fields. */
257 static section *
258 get_noswitch_section (unsigned int flags, noswitch_section_callback callback)
260 section *sect;
262 sect = ggc_alloc<section> ();
263 sect->noswitch.common.flags = flags | SECTION_NOSWITCH;
264 sect->noswitch.callback = callback;
266 return sect;
269 /* Return the named section structure associated with NAME. Create
270 a new section with the given fields if no such structure exists. */
272 section *
273 get_section (const char *name, unsigned int flags, tree decl)
275 section *sect, **slot;
277 slot = (section **)
278 htab_find_slot_with_hash (section_htab, name,
279 htab_hash_string (name), INSERT);
280 flags |= SECTION_NAMED;
281 if (*slot == NULL)
283 sect = ggc_alloc<section> ();
284 sect->named.common.flags = flags;
285 sect->named.name = ggc_strdup (name);
286 sect->named.decl = decl;
287 *slot = sect;
289 else
291 sect = *slot;
292 if ((sect->common.flags & ~SECTION_DECLARED) != flags
293 && ((sect->common.flags | flags) & SECTION_OVERRIDE) == 0)
295 /* It is fine if one of the section flags is
296 SECTION_WRITE | SECTION_RELRO and the other has none of these
297 flags (i.e. read-only) in named sections and either the
298 section hasn't been declared yet or has been declared as writable.
299 In that case just make sure the resulting flags are
300 SECTION_WRITE | SECTION_RELRO, ie. writable only because of
301 relocations. */
302 if (((sect->common.flags ^ flags) & (SECTION_WRITE | SECTION_RELRO))
303 == (SECTION_WRITE | SECTION_RELRO)
304 && (sect->common.flags
305 & ~(SECTION_DECLARED | SECTION_WRITE | SECTION_RELRO))
306 == (flags & ~(SECTION_WRITE | SECTION_RELRO))
307 && ((sect->common.flags & SECTION_DECLARED) == 0
308 || (sect->common.flags & SECTION_WRITE)))
310 sect->common.flags |= (SECTION_WRITE | SECTION_RELRO);
311 return sect;
313 /* Sanity check user variables for flag changes. */
314 if (sect->named.decl != NULL
315 && DECL_P (sect->named.decl)
316 && decl != sect->named.decl)
318 if (decl != NULL && DECL_P (decl))
319 error ("%+D causes a section type conflict with %D",
320 decl, sect->named.decl);
321 else
322 error ("section type conflict with %D", sect->named.decl);
323 inform (DECL_SOURCE_LOCATION (sect->named.decl),
324 "%qD was declared here", sect->named.decl);
326 else if (decl != NULL && DECL_P (decl))
327 error ("%+D causes a section type conflict", decl);
328 else
329 error ("section type conflict");
330 /* Make sure we don't error about one section multiple times. */
331 sect->common.flags |= SECTION_OVERRIDE;
334 return sect;
337 /* Return true if the current compilation mode benefits from having
338 objects grouped into blocks. */
340 static bool
341 use_object_blocks_p (void)
343 return flag_section_anchors;
346 /* Return the object_block structure for section SECT. Create a new
347 structure if we haven't created one already. Return null if SECT
348 itself is null. */
350 static struct object_block *
351 get_block_for_section (section *sect)
353 struct object_block *block;
354 void **slot;
356 if (sect == NULL)
357 return NULL;
359 slot = htab_find_slot_with_hash (object_block_htab, sect,
360 hash_section (sect), INSERT);
361 block = (struct object_block *) *slot;
362 if (block == NULL)
364 block = ggc_cleared_alloc<object_block> ();
365 block->sect = sect;
366 *slot = block;
368 return block;
371 /* Create a symbol with label LABEL and place it at byte offset
372 OFFSET in BLOCK. OFFSET can be negative if the symbol's offset
373 is not yet known. LABEL must be a garbage-collected string. */
375 static rtx
376 create_block_symbol (const char *label, struct object_block *block,
377 HOST_WIDE_INT offset)
379 rtx symbol;
380 unsigned int size;
382 /* Create the extended SYMBOL_REF. */
383 size = RTX_HDR_SIZE + sizeof (struct block_symbol);
384 symbol = (rtx) ggc_internal_alloc (size);
386 /* Initialize the normal SYMBOL_REF fields. */
387 memset (symbol, 0, size);
388 PUT_CODE (symbol, SYMBOL_REF);
389 PUT_MODE (symbol, Pmode);
390 XSTR (symbol, 0) = label;
391 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_HAS_BLOCK_INFO;
393 /* Initialize the block_symbol stuff. */
394 SYMBOL_REF_BLOCK (symbol) = block;
395 SYMBOL_REF_BLOCK_OFFSET (symbol) = offset;
397 return symbol;
400 /* Return a section with a particular name and with whatever SECTION_*
401 flags section_type_flags deems appropriate. The name of the section
402 is taken from NAME if nonnull, otherwise it is taken from DECL's
403 DECL_SECTION_NAME. DECL is the decl associated with the section
404 (see the section comment for details) and RELOC is as for
405 section_type_flags. */
407 section *
408 get_named_section (tree decl, const char *name, int reloc)
410 unsigned int flags;
412 if (name == NULL)
414 gcc_assert (decl && DECL_P (decl) && DECL_SECTION_NAME (decl));
415 name = TREE_STRING_POINTER (DECL_SECTION_NAME (decl));
418 flags = targetm.section_type_flags (decl, name, reloc);
419 return get_section (name, flags, decl);
422 /* If required, set DECL_SECTION_NAME to a unique name. */
424 void
425 resolve_unique_section (tree decl, int reloc ATTRIBUTE_UNUSED,
426 int flag_function_or_data_sections)
428 if (DECL_SECTION_NAME (decl) == NULL_TREE
429 && targetm_common.have_named_sections
430 && (flag_function_or_data_sections
431 || DECL_COMDAT_GROUP (decl)))
433 targetm.asm_out.unique_section (decl, reloc);
434 DECL_HAS_IMPLICIT_SECTION_NAME_P (decl) = true;
438 #ifdef BSS_SECTION_ASM_OP
440 #ifdef ASM_OUTPUT_ALIGNED_BSS
442 /* Utility function for targets to use in implementing
443 ASM_OUTPUT_ALIGNED_BSS.
444 ??? It is believed that this function will work in most cases so such
445 support is localized here. */
447 static void
448 asm_output_aligned_bss (FILE *file, tree decl ATTRIBUTE_UNUSED,
449 const char *name, unsigned HOST_WIDE_INT size,
450 int align)
452 switch_to_section (bss_section);
453 ASM_OUTPUT_ALIGN (file, floor_log2 (align / BITS_PER_UNIT));
454 #ifdef ASM_DECLARE_OBJECT_NAME
455 last_assemble_variable_decl = decl;
456 ASM_DECLARE_OBJECT_NAME (file, name, decl);
457 #else
458 /* Standard thing is just output label for the object. */
459 ASM_OUTPUT_LABEL (file, name);
460 #endif /* ASM_DECLARE_OBJECT_NAME */
461 ASM_OUTPUT_SKIP (file, size ? size : 1);
464 #endif
466 #endif /* BSS_SECTION_ASM_OP */
468 #ifndef USE_SELECT_SECTION_FOR_FUNCTIONS
469 /* Return the hot section for function DECL. Return text_section for
470 null DECLs. */
472 static section *
473 hot_function_section (tree decl)
475 if (decl != NULL_TREE
476 && DECL_SECTION_NAME (decl) != NULL_TREE
477 && targetm_common.have_named_sections)
478 return get_named_section (decl, NULL, 0);
479 else
480 return text_section;
482 #endif
484 /* Return section for TEXT_SECTION_NAME if DECL or DECL_SECTION_NAME (DECL)
485 is NULL.
487 When DECL_SECTION_NAME is non-NULL and it is implicit section and
488 NAMED_SECTION_SUFFIX is non-NULL, then produce section called
489 concatenate the name with NAMED_SECTION_SUFFIX.
490 Otherwise produce "TEXT_SECTION_NAME.IMPLICIT_NAME". */
492 section *
493 get_named_text_section (tree decl,
494 const char *text_section_name,
495 const char *named_section_suffix)
497 if (decl && DECL_SECTION_NAME (decl))
499 if (named_section_suffix)
501 tree dsn = DECL_SECTION_NAME (decl);
502 const char *stripped_name;
503 char *name, *buffer;
505 name = (char *) alloca (TREE_STRING_LENGTH (dsn) + 1);
506 memcpy (name, TREE_STRING_POINTER (dsn),
507 TREE_STRING_LENGTH (dsn) + 1);
509 stripped_name = targetm.strip_name_encoding (name);
511 buffer = ACONCAT ((stripped_name, named_section_suffix, NULL));
512 return get_named_section (decl, buffer, 0);
514 else if (DECL_HAS_IMPLICIT_SECTION_NAME_P (decl))
516 const char *name;
518 /* Do not try to split gnu_linkonce functions. This gets somewhat
519 slipperly. */
520 if (DECL_COMDAT_GROUP (decl) && !HAVE_COMDAT_GROUP)
521 return NULL;
522 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
523 name = targetm.strip_name_encoding (name);
524 return get_named_section (decl, ACONCAT ((text_section_name, ".",
525 name, NULL)), 0);
527 else
528 return NULL;
530 return get_named_section (decl, text_section_name, 0);
533 /* Choose named function section based on its frequency. */
535 section *
536 default_function_section (tree decl, enum node_frequency freq,
537 bool startup, bool exit)
539 #if defined HAVE_LD_EH_GC_SECTIONS && defined HAVE_LD_EH_GC_SECTIONS_BUG
540 /* Old GNU linkers have buggy --gc-section support, which sometimes
541 results in .gcc_except_table* sections being garbage collected. */
542 if (decl
543 && DECL_SECTION_NAME (decl)
544 && DECL_HAS_IMPLICIT_SECTION_NAME_P (decl))
545 return NULL;
546 #endif
548 if (!flag_reorder_functions
549 || !targetm_common.have_named_sections)
550 return NULL;
551 /* Startup code should go to startup subsection unless it is
552 unlikely executed (this happens especially with function splitting
553 where we can split away unnecessary parts of static constructors. */
554 if (startup && freq != NODE_FREQUENCY_UNLIKELY_EXECUTED)
556 /* If we do have a profile or(and) LTO phase is executed, we do not need
557 these ELF section. */
558 if (!in_lto_p || !flag_profile_values)
559 return get_named_text_section (decl, ".text.startup", NULL);
560 else
561 return NULL;
564 /* Similarly for exit. */
565 if (exit && freq != NODE_FREQUENCY_UNLIKELY_EXECUTED)
566 return get_named_text_section (decl, ".text.exit", NULL);
568 /* Group cold functions together, similarly for hot code. */
569 switch (freq)
571 case NODE_FREQUENCY_UNLIKELY_EXECUTED:
572 return get_named_text_section (decl, ".text.unlikely", NULL);
573 case NODE_FREQUENCY_HOT:
574 /* If we do have a profile or(and) LTO phase is executed, we do not need
575 these ELF section. */
576 if (!in_lto_p || !flag_profile_values)
577 return get_named_text_section (decl, ".text.hot", NULL);
578 default:
579 return NULL;
583 /* Return the section for function DECL.
585 If DECL is NULL_TREE, return the text section. We can be passed
586 NULL_TREE under some circumstances by dbxout.c at least.
588 If FORCE_COLD is true, return cold function section ignoring
589 the frequency info of cgraph_node. */
591 static section *
592 function_section_1 (tree decl, bool force_cold)
594 section *section = NULL;
595 enum node_frequency freq = NODE_FREQUENCY_NORMAL;
596 bool startup = false, exit = false;
598 if (decl)
600 struct cgraph_node *node = cgraph_get_node (decl);
602 if (node)
604 freq = node->frequency;
605 startup = node->only_called_at_startup;
606 exit = node->only_called_at_exit;
609 if (force_cold)
610 freq = NODE_FREQUENCY_UNLIKELY_EXECUTED;
612 #ifdef USE_SELECT_SECTION_FOR_FUNCTIONS
613 if (decl != NULL_TREE
614 && DECL_SECTION_NAME (decl) != NULL_TREE)
616 if (targetm.asm_out.function_section)
617 section = targetm.asm_out.function_section (decl, freq,
618 startup, exit);
619 if (section)
620 return section;
621 return get_named_section (decl, NULL, 0);
623 else
624 return targetm.asm_out.select_section
625 (decl, freq == NODE_FREQUENCY_UNLIKELY_EXECUTED,
626 DECL_ALIGN (decl));
627 #else
628 if (targetm.asm_out.function_section)
629 section = targetm.asm_out.function_section (decl, freq, startup, exit);
630 if (section)
631 return section;
632 return hot_function_section (decl);
633 #endif
636 /* Return the section for function DECL.
638 If DECL is NULL_TREE, return the text section. We can be passed
639 NULL_TREE under some circumstances by dbxout.c at least. */
641 section *
642 function_section (tree decl)
644 /* Handle cases where function splitting code decides
645 to put function entry point into unlikely executed section
646 despite the fact that the function itself is not cold
647 (i.e. it is called rarely but contains a hot loop that is
648 better to live in hot subsection for the code locality). */
649 return function_section_1 (decl,
650 first_function_block_is_cold);
653 /* Return the section for the current function, take IN_COLD_SECTION_P
654 into account. */
656 section *
657 current_function_section (void)
659 return function_section_1 (current_function_decl, in_cold_section_p);
662 /* Tell assembler to switch to unlikely-to-be-executed text section. */
664 section *
665 unlikely_text_section (void)
667 return function_section_1 (current_function_decl, true);
670 /* When called within a function context, return true if the function
671 has been assigned a cold text section and if SECT is that section.
672 When called outside a function context, return true if SECT is the
673 default cold section. */
675 bool
676 unlikely_text_section_p (section *sect)
678 return sect == function_section_1 (current_function_decl, true);
681 /* Return the read-only data section associated with function DECL. */
683 section *
684 default_function_rodata_section (tree decl)
686 if (decl != NULL_TREE && DECL_SECTION_NAME (decl))
688 const char *name = TREE_STRING_POINTER (DECL_SECTION_NAME (decl));
690 if (DECL_COMDAT_GROUP (decl) && HAVE_COMDAT_GROUP)
692 const char *dot;
693 size_t len;
694 char* rname;
696 dot = strchr (name + 1, '.');
697 if (!dot)
698 dot = name;
699 len = strlen (dot) + 8;
700 rname = (char *) alloca (len);
702 strcpy (rname, ".rodata");
703 strcat (rname, dot);
704 return get_section (rname, SECTION_LINKONCE, decl);
706 /* For .gnu.linkonce.t.foo we want to use .gnu.linkonce.r.foo. */
707 else if (DECL_COMDAT_GROUP (decl)
708 && strncmp (name, ".gnu.linkonce.t.", 16) == 0)
710 size_t len = strlen (name) + 1;
711 char *rname = (char *) alloca (len);
713 memcpy (rname, name, len);
714 rname[14] = 'r';
715 return get_section (rname, SECTION_LINKONCE, decl);
717 /* For .text.foo we want to use .rodata.foo. */
718 else if (flag_function_sections && flag_data_sections
719 && strncmp (name, ".text.", 6) == 0)
721 size_t len = strlen (name) + 1;
722 char *rname = (char *) alloca (len + 2);
724 memcpy (rname, ".rodata", 7);
725 memcpy (rname + 7, name + 5, len - 5);
726 return get_section (rname, 0, decl);
730 return readonly_data_section;
733 /* Return the read-only data section associated with function DECL
734 for targets where that section should be always the single
735 readonly data section. */
737 section *
738 default_no_function_rodata_section (tree decl ATTRIBUTE_UNUSED)
740 return readonly_data_section;
743 /* Return the section to use for string merging. */
745 static section *
746 mergeable_string_section (tree decl ATTRIBUTE_UNUSED,
747 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
748 unsigned int flags ATTRIBUTE_UNUSED)
750 HOST_WIDE_INT len;
752 if (HAVE_GAS_SHF_MERGE && flag_merge_constants
753 && TREE_CODE (decl) == STRING_CST
754 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
755 && align <= 256
756 && (len = int_size_in_bytes (TREE_TYPE (decl))) > 0
757 && TREE_STRING_LENGTH (decl) >= len)
759 enum machine_mode mode;
760 unsigned int modesize;
761 const char *str;
762 HOST_WIDE_INT i;
763 int j, unit;
764 const char *prefix = targetm.asm_out.mergeable_rodata_prefix;
765 char *name = (char *) alloca (strlen (prefix) + 30);
767 mode = TYPE_MODE (TREE_TYPE (TREE_TYPE (decl)));
768 modesize = GET_MODE_BITSIZE (mode);
769 if (modesize >= 8 && modesize <= 256
770 && (modesize & (modesize - 1)) == 0)
772 if (align < modesize)
773 align = modesize;
775 str = TREE_STRING_POINTER (decl);
776 unit = GET_MODE_SIZE (mode);
778 /* Check for embedded NUL characters. */
779 for (i = 0; i < len; i += unit)
781 for (j = 0; j < unit; j++)
782 if (str[i + j] != '\0')
783 break;
784 if (j == unit)
785 break;
787 if (i == len - unit)
789 sprintf (name, "%s.str%d.%d", prefix,
790 modesize / 8, (int) (align / 8));
791 flags |= (modesize / 8) | SECTION_MERGE | SECTION_STRINGS;
792 return get_section (name, flags, NULL);
797 return readonly_data_section;
800 /* Return the section to use for constant merging. */
802 section *
803 mergeable_constant_section (enum machine_mode mode ATTRIBUTE_UNUSED,
804 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
805 unsigned int flags ATTRIBUTE_UNUSED)
807 unsigned int modesize = GET_MODE_BITSIZE (mode);
809 if (HAVE_GAS_SHF_MERGE && flag_merge_constants
810 && mode != VOIDmode
811 && mode != BLKmode
812 && modesize <= align
813 && align >= 8
814 && align <= 256
815 && (align & (align - 1)) == 0)
817 const char *prefix = targetm.asm_out.mergeable_rodata_prefix;
818 char *name = (char *) alloca (strlen (prefix) + 30);
820 sprintf (name, "%s.cst%d", prefix, (int) (align / 8));
821 flags |= (align / 8) | SECTION_MERGE;
822 return get_section (name, flags, NULL);
824 return readonly_data_section;
827 /* Given NAME, a putative register name, discard any customary prefixes. */
829 static const char *
830 strip_reg_name (const char *name)
832 #ifdef REGISTER_PREFIX
833 if (!strncmp (name, REGISTER_PREFIX, strlen (REGISTER_PREFIX)))
834 name += strlen (REGISTER_PREFIX);
835 #endif
836 if (name[0] == '%' || name[0] == '#')
837 name++;
838 return name;
841 /* The user has asked for a DECL to have a particular name. Set (or
842 change) it in such a way that we don't prefix an underscore to
843 it. */
844 void
845 set_user_assembler_name (tree decl, const char *name)
847 char *starred = (char *) alloca (strlen (name) + 2);
848 starred[0] = '*';
849 strcpy (starred + 1, name);
850 change_decl_assembler_name (decl, get_identifier (starred));
851 SET_DECL_RTL (decl, NULL_RTX);
854 /* Decode an `asm' spec for a declaration as a register name.
855 Return the register number, or -1 if nothing specified,
856 or -2 if the ASMSPEC is not `cc' or `memory' and is not recognized,
857 or -3 if ASMSPEC is `cc' and is not recognized,
858 or -4 if ASMSPEC is `memory' and is not recognized.
859 Accept an exact spelling or a decimal number.
860 Prefixes such as % are optional. */
863 decode_reg_name_and_count (const char *asmspec, int *pnregs)
865 /* Presume just one register is clobbered. */
866 *pnregs = 1;
868 if (asmspec != 0)
870 int i;
872 /* Get rid of confusing prefixes. */
873 asmspec = strip_reg_name (asmspec);
875 /* Allow a decimal number as a "register name". */
876 for (i = strlen (asmspec) - 1; i >= 0; i--)
877 if (! ISDIGIT (asmspec[i]))
878 break;
879 if (asmspec[0] != 0 && i < 0)
881 i = atoi (asmspec);
882 if (i < FIRST_PSEUDO_REGISTER && i >= 0)
883 return i;
884 else
885 return -2;
888 for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
889 if (reg_names[i][0]
890 && ! strcmp (asmspec, strip_reg_name (reg_names[i])))
891 return i;
893 #ifdef OVERLAPPING_REGISTER_NAMES
895 static const struct
897 const char *const name;
898 const int number;
899 const int nregs;
900 } table[] = OVERLAPPING_REGISTER_NAMES;
902 for (i = 0; i < (int) ARRAY_SIZE (table); i++)
903 if (table[i].name[0]
904 && ! strcmp (asmspec, table[i].name))
906 *pnregs = table[i].nregs;
907 return table[i].number;
910 #endif /* OVERLAPPING_REGISTER_NAMES */
912 #ifdef ADDITIONAL_REGISTER_NAMES
914 static const struct { const char *const name; const int number; } table[]
915 = ADDITIONAL_REGISTER_NAMES;
917 for (i = 0; i < (int) ARRAY_SIZE (table); i++)
918 if (table[i].name[0]
919 && ! strcmp (asmspec, table[i].name))
920 return table[i].number;
922 #endif /* ADDITIONAL_REGISTER_NAMES */
924 if (!strcmp (asmspec, "memory"))
925 return -4;
927 if (!strcmp (asmspec, "cc"))
928 return -3;
930 return -2;
933 return -1;
937 decode_reg_name (const char *name)
939 int count;
940 return decode_reg_name_and_count (name, &count);
944 /* Return true if DECL's initializer is suitable for a BSS section. */
946 bool
947 bss_initializer_p (const_tree decl)
949 return (DECL_INITIAL (decl) == NULL
950 || DECL_INITIAL (decl) == error_mark_node
951 || (flag_zero_initialized_in_bss
952 /* Leave constant zeroes in .rodata so they
953 can be shared. */
954 && !TREE_READONLY (decl)
955 && initializer_zerop (DECL_INITIAL (decl))));
958 /* Compute the alignment of variable specified by DECL.
959 DONT_OUTPUT_DATA is from assemble_variable. */
961 void
962 align_variable (tree decl, bool dont_output_data)
964 unsigned int align = DECL_ALIGN (decl);
966 /* In the case for initialing an array whose length isn't specified,
967 where we have not yet been able to do the layout,
968 figure out the proper alignment now. */
969 if (dont_output_data && DECL_SIZE (decl) == 0
970 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE)
971 align = MAX (align, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (decl))));
973 /* Some object file formats have a maximum alignment which they support.
974 In particular, a.out format supports a maximum alignment of 4. */
975 if (align > MAX_OFILE_ALIGNMENT)
977 error ("alignment of %q+D is greater than maximum object "
978 "file alignment %d", decl,
979 MAX_OFILE_ALIGNMENT/BITS_PER_UNIT);
980 align = MAX_OFILE_ALIGNMENT;
983 if (! DECL_USER_ALIGN (decl))
985 #ifdef DATA_ABI_ALIGNMENT
986 unsigned int data_abi_align
987 = DATA_ABI_ALIGNMENT (TREE_TYPE (decl), align);
988 /* For backwards compatibility, don't assume the ABI alignment for
989 TLS variables. */
990 if (! DECL_THREAD_LOCAL_P (decl) || data_abi_align <= BITS_PER_WORD)
991 align = data_abi_align;
992 #endif
994 /* On some machines, it is good to increase alignment sometimes.
995 But as DECL_ALIGN is used both for actually emitting the variable
996 and for code accessing the variable as guaranteed alignment, we
997 can only increase the alignment if it is a performance optimization
998 if the references to it must bind to the current definition. */
999 if (decl_binds_to_current_def_p (decl)
1000 && !DECL_VIRTUAL_P (decl))
1002 #ifdef DATA_ALIGNMENT
1003 unsigned int data_align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
1004 /* Don't increase alignment too much for TLS variables - TLS space
1005 is too precious. */
1006 if (! DECL_THREAD_LOCAL_P (decl) || data_align <= BITS_PER_WORD)
1007 align = data_align;
1008 #endif
1009 #ifdef CONSTANT_ALIGNMENT
1010 if (DECL_INITIAL (decl) != 0
1011 && DECL_INITIAL (decl) != error_mark_node)
1013 unsigned int const_align
1014 = CONSTANT_ALIGNMENT (DECL_INITIAL (decl), align);
1015 /* Don't increase alignment too much for TLS variables - TLS
1016 space is too precious. */
1017 if (! DECL_THREAD_LOCAL_P (decl) || const_align <= BITS_PER_WORD)
1018 align = const_align;
1020 #endif
1024 /* Reset the alignment in case we have made it tighter, so we can benefit
1025 from it in get_pointer_alignment. */
1026 DECL_ALIGN (decl) = align;
1029 /* Return DECL_ALIGN (decl), possibly increased for optimization purposes
1030 beyond what align_variable returned. */
1032 static unsigned int
1033 get_variable_align (tree decl)
1035 unsigned int align = DECL_ALIGN (decl);
1037 /* For user aligned vars or static vars align_variable already did
1038 everything. */
1039 if (DECL_USER_ALIGN (decl) || !TREE_PUBLIC (decl))
1040 return align;
1042 #ifdef DATA_ABI_ALIGNMENT
1043 if (DECL_THREAD_LOCAL_P (decl))
1044 align = DATA_ABI_ALIGNMENT (TREE_TYPE (decl), align);
1045 #endif
1047 /* For decls that bind to the current definition, align_variable
1048 did also everything, except for not assuming ABI required alignment
1049 of TLS variables. For other vars, increase the alignment here
1050 as an optimization. */
1051 if (!decl_binds_to_current_def_p (decl))
1053 /* On some machines, it is good to increase alignment sometimes. */
1054 #ifdef DATA_ALIGNMENT
1055 unsigned int data_align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
1056 /* Don't increase alignment too much for TLS variables - TLS space
1057 is too precious. */
1058 if (! DECL_THREAD_LOCAL_P (decl) || data_align <= BITS_PER_WORD)
1059 align = data_align;
1060 #endif
1061 #ifdef CONSTANT_ALIGNMENT
1062 if (DECL_INITIAL (decl) != 0 && DECL_INITIAL (decl) != error_mark_node)
1064 unsigned int const_align = CONSTANT_ALIGNMENT (DECL_INITIAL (decl),
1065 align);
1066 /* Don't increase alignment too much for TLS variables - TLS space
1067 is too precious. */
1068 if (! DECL_THREAD_LOCAL_P (decl) || const_align <= BITS_PER_WORD)
1069 align = const_align;
1071 #endif
1074 return align;
1077 /* Return the section into which the given VAR_DECL or CONST_DECL
1078 should be placed. PREFER_NOSWITCH_P is true if a noswitch
1079 section should be used wherever possible. */
1081 section *
1082 get_variable_section (tree decl, bool prefer_noswitch_p)
1084 addr_space_t as = ADDR_SPACE_GENERIC;
1085 int reloc;
1087 if (TREE_TYPE (decl) != error_mark_node)
1088 as = TYPE_ADDR_SPACE (TREE_TYPE (decl));
1090 if (DECL_COMMON (decl))
1092 /* If the decl has been given an explicit section name, or it resides
1093 in a non-generic address space, then it isn't common, and shouldn't
1094 be handled as such. */
1095 gcc_assert (DECL_SECTION_NAME (decl) == NULL
1096 && ADDR_SPACE_GENERIC_P (as));
1097 if (DECL_THREAD_LOCAL_P (decl))
1098 return tls_comm_section;
1099 else if (TREE_PUBLIC (decl) && bss_initializer_p (decl))
1100 return comm_section;
1103 if (DECL_INITIAL (decl) == error_mark_node)
1104 reloc = contains_pointers_p (TREE_TYPE (decl)) ? 3 : 0;
1105 else if (DECL_INITIAL (decl))
1106 reloc = compute_reloc_for_constant (DECL_INITIAL (decl));
1107 else
1108 reloc = 0;
1110 resolve_unique_section (decl, reloc, flag_data_sections);
1111 if (IN_NAMED_SECTION (decl))
1112 return get_named_section (decl, NULL, reloc);
1114 if (ADDR_SPACE_GENERIC_P (as)
1115 && !DECL_THREAD_LOCAL_P (decl)
1116 && !(prefer_noswitch_p && targetm.have_switchable_bss_sections)
1117 && bss_initializer_p (decl))
1119 if (!TREE_PUBLIC (decl)
1120 && !((flag_sanitize & SANITIZE_ADDRESS)
1121 && asan_protect_global (decl)))
1122 return lcomm_section;
1123 if (bss_noswitch_section)
1124 return bss_noswitch_section;
1127 return targetm.asm_out.select_section (decl, reloc,
1128 get_variable_align (decl));
1131 /* Return the block into which object_block DECL should be placed. */
1133 static struct object_block *
1134 get_block_for_decl (tree decl)
1136 section *sect;
1138 if (TREE_CODE (decl) == VAR_DECL)
1140 /* The object must be defined in this translation unit. */
1141 if (DECL_EXTERNAL (decl))
1142 return NULL;
1144 /* There's no point using object blocks for something that is
1145 isolated by definition. */
1146 if (DECL_COMDAT_GROUP (decl))
1147 return NULL;
1150 /* We can only calculate block offsets if the decl has a known
1151 constant size. */
1152 if (DECL_SIZE_UNIT (decl) == NULL)
1153 return NULL;
1154 if (!tree_fits_uhwi_p (DECL_SIZE_UNIT (decl)))
1155 return NULL;
1157 /* Find out which section should contain DECL. We cannot put it into
1158 an object block if it requires a standalone definition. */
1159 if (TREE_CODE (decl) == VAR_DECL)
1160 align_variable (decl, 0);
1161 sect = get_variable_section (decl, true);
1162 if (SECTION_STYLE (sect) == SECTION_NOSWITCH)
1163 return NULL;
1165 return get_block_for_section (sect);
1168 /* Make sure block symbol SYMBOL is in block BLOCK. */
1170 static void
1171 change_symbol_block (rtx symbol, struct object_block *block)
1173 if (block != SYMBOL_REF_BLOCK (symbol))
1175 gcc_assert (SYMBOL_REF_BLOCK_OFFSET (symbol) < 0);
1176 SYMBOL_REF_BLOCK (symbol) = block;
1180 /* Return true if it is possible to put DECL in an object_block. */
1182 static bool
1183 use_blocks_for_decl_p (tree decl)
1185 /* Only data DECLs can be placed into object blocks. */
1186 if (TREE_CODE (decl) != VAR_DECL && TREE_CODE (decl) != CONST_DECL)
1187 return false;
1189 /* Detect decls created by dw2_force_const_mem. Such decls are
1190 special because DECL_INITIAL doesn't specify the decl's true value.
1191 dw2_output_indirect_constants will instead call assemble_variable
1192 with dont_output_data set to 1 and then print the contents itself. */
1193 if (DECL_INITIAL (decl) == decl)
1194 return false;
1196 /* If this decl is an alias, then we don't want to emit a
1197 definition. */
1198 if (lookup_attribute ("alias", DECL_ATTRIBUTES (decl)))
1199 return false;
1201 return targetm.use_blocks_for_decl_p (decl);
1204 /* Create the DECL_RTL for a VAR_DECL or FUNCTION_DECL. DECL should
1205 have static storage duration. In other words, it should not be an
1206 automatic variable, including PARM_DECLs.
1208 There is, however, one exception: this function handles variables
1209 explicitly placed in a particular register by the user.
1211 This is never called for PARM_DECL nodes. */
1213 void
1214 make_decl_rtl (tree decl)
1216 const char *name = 0;
1217 int reg_number;
1218 rtx x;
1220 /* Check that we are not being given an automatic variable. */
1221 gcc_assert (TREE_CODE (decl) != PARM_DECL
1222 && TREE_CODE (decl) != RESULT_DECL);
1224 /* A weak alias has TREE_PUBLIC set but not the other bits. */
1225 gcc_assert (TREE_CODE (decl) != VAR_DECL
1226 || TREE_STATIC (decl)
1227 || TREE_PUBLIC (decl)
1228 || DECL_EXTERNAL (decl)
1229 || DECL_REGISTER (decl));
1231 /* And that we were not given a type or a label. */
1232 gcc_assert (TREE_CODE (decl) != TYPE_DECL
1233 && TREE_CODE (decl) != LABEL_DECL);
1235 /* For a duplicate declaration, we can be called twice on the
1236 same DECL node. Don't discard the RTL already made. */
1237 if (DECL_RTL_SET_P (decl))
1239 /* If the old RTL had the wrong mode, fix the mode. */
1240 x = DECL_RTL (decl);
1241 if (GET_MODE (x) != DECL_MODE (decl))
1242 SET_DECL_RTL (decl, adjust_address_nv (x, DECL_MODE (decl), 0));
1244 if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
1245 return;
1247 /* ??? Another way to do this would be to maintain a hashed
1248 table of such critters. Instead of adding stuff to a DECL
1249 to give certain attributes to it, we could use an external
1250 hash map from DECL to set of attributes. */
1252 /* Let the target reassign the RTL if it wants.
1253 This is necessary, for example, when one machine specific
1254 decl attribute overrides another. */
1255 targetm.encode_section_info (decl, DECL_RTL (decl), false);
1257 /* If the symbol has a SYMBOL_REF_BLOCK field, update it based
1258 on the new decl information. */
1259 if (MEM_P (x)
1260 && GET_CODE (XEXP (x, 0)) == SYMBOL_REF
1261 && SYMBOL_REF_HAS_BLOCK_INFO_P (XEXP (x, 0)))
1262 change_symbol_block (XEXP (x, 0), get_block_for_decl (decl));
1264 return;
1267 /* If this variable belongs to the global constant pool, retrieve the
1268 pre-computed RTL or recompute it in LTO mode. */
1269 if (TREE_CODE (decl) == VAR_DECL && DECL_IN_CONSTANT_POOL (decl))
1271 SET_DECL_RTL (decl, output_constant_def (DECL_INITIAL (decl), 1));
1272 return;
1275 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
1277 if (name[0] != '*' && TREE_CODE (decl) != FUNCTION_DECL
1278 && DECL_REGISTER (decl))
1280 error ("register name not specified for %q+D", decl);
1282 else if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
1284 const char *asmspec = name+1;
1285 enum machine_mode mode = DECL_MODE (decl);
1286 reg_number = decode_reg_name (asmspec);
1287 /* First detect errors in declaring global registers. */
1288 if (reg_number == -1)
1289 error ("register name not specified for %q+D", decl);
1290 else if (reg_number < 0)
1291 error ("invalid register name for %q+D", decl);
1292 else if (mode == BLKmode)
1293 error ("data type of %q+D isn%'t suitable for a register",
1294 decl);
1295 else if (!in_hard_reg_set_p (accessible_reg_set, mode, reg_number))
1296 error ("the register specified for %q+D cannot be accessed"
1297 " by the current target", decl);
1298 else if (!in_hard_reg_set_p (operand_reg_set, mode, reg_number))
1299 error ("the register specified for %q+D is not general enough"
1300 " to be used as a register variable", decl);
1301 else if (!HARD_REGNO_MODE_OK (reg_number, mode))
1302 error ("register specified for %q+D isn%'t suitable for data type",
1303 decl);
1304 /* Now handle properly declared static register variables. */
1305 else
1307 int nregs;
1309 if (DECL_INITIAL (decl) != 0 && TREE_STATIC (decl))
1311 DECL_INITIAL (decl) = 0;
1312 error ("global register variable has initial value");
1314 if (TREE_THIS_VOLATILE (decl))
1315 warning (OPT_Wvolatile_register_var,
1316 "optimization may eliminate reads and/or "
1317 "writes to register variables");
1319 /* If the user specified one of the eliminables registers here,
1320 e.g., FRAME_POINTER_REGNUM, we don't want to get this variable
1321 confused with that register and be eliminated. This usage is
1322 somewhat suspect... */
1324 SET_DECL_RTL (decl, gen_rtx_raw_REG (mode, reg_number));
1325 ORIGINAL_REGNO (DECL_RTL (decl)) = reg_number;
1326 REG_USERVAR_P (DECL_RTL (decl)) = 1;
1328 if (TREE_STATIC (decl))
1330 /* Make this register global, so not usable for anything
1331 else. */
1332 #ifdef ASM_DECLARE_REGISTER_GLOBAL
1333 name = IDENTIFIER_POINTER (DECL_NAME (decl));
1334 ASM_DECLARE_REGISTER_GLOBAL (asm_out_file, decl, reg_number, name);
1335 #endif
1336 nregs = hard_regno_nregs[reg_number][mode];
1337 while (nregs > 0)
1338 globalize_reg (decl, reg_number + --nregs);
1341 /* As a register variable, it has no section. */
1342 return;
1345 /* Now handle ordinary static variables and functions (in memory).
1346 Also handle vars declared register invalidly. */
1347 else if (name[0] == '*')
1349 #ifdef REGISTER_PREFIX
1350 if (strlen (REGISTER_PREFIX) != 0)
1352 reg_number = decode_reg_name (name);
1353 if (reg_number >= 0 || reg_number == -3)
1354 error ("register name given for non-register variable %q+D", decl);
1356 #endif
1359 /* Specifying a section attribute on a variable forces it into a
1360 non-.bss section, and thus it cannot be common. */
1361 /* FIXME: In general this code should not be necessary because
1362 visibility pass is doing the same work. But notice_global_symbol
1363 is called early and it needs to make DECL_RTL to get the name.
1364 we take care of recomputing the DECL_RTL after visibility is changed. */
1365 if (TREE_CODE (decl) == VAR_DECL
1366 && DECL_SECTION_NAME (decl) != NULL_TREE
1367 && DECL_INITIAL (decl) == NULL_TREE
1368 && DECL_COMMON (decl))
1369 DECL_COMMON (decl) = 0;
1371 /* Variables can't be both common and weak. */
1372 if (TREE_CODE (decl) == VAR_DECL && DECL_WEAK (decl))
1373 DECL_COMMON (decl) = 0;
1375 if (use_object_blocks_p () && use_blocks_for_decl_p (decl))
1376 x = create_block_symbol (name, get_block_for_decl (decl), -1);
1377 else
1379 enum machine_mode address_mode = Pmode;
1380 if (TREE_TYPE (decl) != error_mark_node)
1382 addr_space_t as = TYPE_ADDR_SPACE (TREE_TYPE (decl));
1383 address_mode = targetm.addr_space.address_mode (as);
1385 x = gen_rtx_SYMBOL_REF (address_mode, name);
1387 SYMBOL_REF_WEAK (x) = DECL_WEAK (decl);
1388 SET_SYMBOL_REF_DECL (x, decl);
1390 x = gen_rtx_MEM (DECL_MODE (decl), x);
1391 if (TREE_CODE (decl) != FUNCTION_DECL)
1392 set_mem_attributes (x, decl, 1);
1393 SET_DECL_RTL (decl, x);
1395 /* Optionally set flags or add text to the name to record information
1396 such as that it is a function name.
1397 If the name is changed, the macro ASM_OUTPUT_LABELREF
1398 will have to know how to strip this information. */
1399 targetm.encode_section_info (decl, DECL_RTL (decl), true);
1402 /* Like make_decl_rtl, but inhibit creation of new alias sets when
1403 calling make_decl_rtl. Also, reset DECL_RTL before returning the
1404 rtl. */
1407 make_decl_rtl_for_debug (tree decl)
1409 unsigned int save_aliasing_flag;
1410 rtx rtl;
1412 if (DECL_RTL_SET_P (decl))
1413 return DECL_RTL (decl);
1415 /* Kludge alert! Somewhere down the call chain, make_decl_rtl will
1416 call new_alias_set. If running with -fcompare-debug, sometimes
1417 we do not want to create alias sets that will throw the alias
1418 numbers off in the comparison dumps. So... clearing
1419 flag_strict_aliasing will keep new_alias_set() from creating a
1420 new set. */
1421 save_aliasing_flag = flag_strict_aliasing;
1422 flag_strict_aliasing = 0;
1424 rtl = DECL_RTL (decl);
1425 /* Reset DECL_RTL back, as various parts of the compiler expects
1426 DECL_RTL set meaning it is actually going to be output. */
1427 SET_DECL_RTL (decl, NULL);
1429 flag_strict_aliasing = save_aliasing_flag;
1430 return rtl;
1433 /* Output a string of literal assembler code
1434 for an `asm' keyword used between functions. */
1436 void
1437 assemble_asm (tree string)
1439 const char *p;
1440 app_enable ();
1442 if (TREE_CODE (string) == ADDR_EXPR)
1443 string = TREE_OPERAND (string, 0);
1445 p = TREE_STRING_POINTER (string);
1446 fprintf (asm_out_file, "%s%s\n", p[0] == '\t' ? "" : "\t", p);
1449 /* Write the address of the entity given by SYMBOL to SEC. */
1450 void
1451 assemble_addr_to_section (rtx symbol, section *sec)
1453 switch_to_section (sec);
1454 assemble_align (POINTER_SIZE);
1455 assemble_integer (symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
1458 /* Return the numbered .ctors.N (if CONSTRUCTOR_P) or .dtors.N (if
1459 not) section for PRIORITY. */
1460 section *
1461 get_cdtor_priority_section (int priority, bool constructor_p)
1463 char buf[16];
1465 /* ??? This only works reliably with the GNU linker. */
1466 sprintf (buf, "%s.%.5u",
1467 constructor_p ? ".ctors" : ".dtors",
1468 /* Invert the numbering so the linker puts us in the proper
1469 order; constructors are run from right to left, and the
1470 linker sorts in increasing order. */
1471 MAX_INIT_PRIORITY - priority);
1472 return get_section (buf, SECTION_WRITE, NULL);
1475 void
1476 default_named_section_asm_out_destructor (rtx symbol, int priority)
1478 section *sec;
1480 if (priority != DEFAULT_INIT_PRIORITY)
1481 sec = get_cdtor_priority_section (priority,
1482 /*constructor_p=*/false);
1483 else
1484 sec = get_section (".dtors", SECTION_WRITE, NULL);
1486 assemble_addr_to_section (symbol, sec);
1489 #ifdef DTORS_SECTION_ASM_OP
1490 void
1491 default_dtor_section_asm_out_destructor (rtx symbol,
1492 int priority ATTRIBUTE_UNUSED)
1494 assemble_addr_to_section (symbol, dtors_section);
1496 #endif
1498 void
1499 default_named_section_asm_out_constructor (rtx symbol, int priority)
1501 section *sec;
1503 if (priority != DEFAULT_INIT_PRIORITY)
1504 sec = get_cdtor_priority_section (priority,
1505 /*constructor_p=*/true);
1506 else
1507 sec = get_section (".ctors", SECTION_WRITE, NULL);
1509 assemble_addr_to_section (symbol, sec);
1512 #ifdef CTORS_SECTION_ASM_OP
1513 void
1514 default_ctor_section_asm_out_constructor (rtx symbol,
1515 int priority ATTRIBUTE_UNUSED)
1517 assemble_addr_to_section (symbol, ctors_section);
1519 #endif
1521 /* CONSTANT_POOL_BEFORE_FUNCTION may be defined as an expression with
1522 a nonzero value if the constant pool should be output before the
1523 start of the function, or a zero value if the pool should output
1524 after the end of the function. The default is to put it before the
1525 start. */
1527 #ifndef CONSTANT_POOL_BEFORE_FUNCTION
1528 #define CONSTANT_POOL_BEFORE_FUNCTION 1
1529 #endif
1531 /* DECL is an object (either VAR_DECL or FUNCTION_DECL) which is going
1532 to be output to assembler.
1533 Set first_global_object_name and weak_global_object_name as appropriate. */
1535 void
1536 notice_global_symbol (tree decl)
1538 const char **type = &first_global_object_name;
1540 if (first_global_object_name
1541 || !TREE_PUBLIC (decl)
1542 || DECL_EXTERNAL (decl)
1543 || !DECL_NAME (decl)
1544 || (TREE_CODE (decl) != FUNCTION_DECL
1545 && (TREE_CODE (decl) != VAR_DECL
1546 || (DECL_COMMON (decl)
1547 && (DECL_INITIAL (decl) == 0
1548 || DECL_INITIAL (decl) == error_mark_node))))
1549 || !MEM_P (DECL_RTL (decl)))
1550 return;
1552 /* We win when global object is found, but it is useful to know about weak
1553 symbol as well so we can produce nicer unique names. */
1554 if (DECL_WEAK (decl) || DECL_ONE_ONLY (decl) || flag_shlib)
1555 type = &weak_global_object_name;
1557 if (!*type)
1559 const char *p;
1560 const char *name;
1561 rtx decl_rtl = DECL_RTL (decl);
1563 p = targetm.strip_name_encoding (XSTR (XEXP (decl_rtl, 0), 0));
1564 name = ggc_strdup (p);
1566 *type = name;
1570 /* If not using flag_reorder_blocks_and_partition, decide early whether the
1571 current function goes into the cold section, so that targets can use
1572 current_function_section during RTL expansion. DECL describes the
1573 function. */
1575 void
1576 decide_function_section (tree decl)
1578 first_function_block_is_cold = false;
1580 if (flag_reorder_blocks_and_partition)
1581 /* We will decide in assemble_start_function. */
1582 return;
1584 if (DECL_SECTION_NAME (decl))
1586 struct cgraph_node *node = cgraph_get_node (current_function_decl);
1587 /* Calls to function_section rely on first_function_block_is_cold
1588 being accurate. */
1589 first_function_block_is_cold = (node
1590 && node->frequency
1591 == NODE_FREQUENCY_UNLIKELY_EXECUTED);
1594 in_cold_section_p = first_function_block_is_cold;
1597 /* Output assembler code for the constant pool of a function and associated
1598 with defining the name of the function. DECL describes the function.
1599 NAME is the function's name. For the constant pool, we use the current
1600 constant pool data. */
1602 void
1603 assemble_start_function (tree decl, const char *fnname)
1605 int align;
1606 char tmp_label[100];
1607 bool hot_label_written = false;
1609 if (flag_reorder_blocks_and_partition)
1611 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LHOTB", const_labelno);
1612 crtl->subsections.hot_section_label = ggc_strdup (tmp_label);
1613 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LCOLDB", const_labelno);
1614 crtl->subsections.cold_section_label = ggc_strdup (tmp_label);
1615 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LHOTE", const_labelno);
1616 crtl->subsections.hot_section_end_label = ggc_strdup (tmp_label);
1617 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LCOLDE", const_labelno);
1618 crtl->subsections.cold_section_end_label = ggc_strdup (tmp_label);
1619 const_labelno++;
1621 else
1623 crtl->subsections.hot_section_label = NULL;
1624 crtl->subsections.cold_section_label = NULL;
1625 crtl->subsections.hot_section_end_label = NULL;
1626 crtl->subsections.cold_section_end_label = NULL;
1629 /* The following code does not need preprocessing in the assembler. */
1631 app_disable ();
1633 if (CONSTANT_POOL_BEFORE_FUNCTION)
1634 output_constant_pool (fnname, decl);
1636 /* Make sure the not and cold text (code) sections are properly
1637 aligned. This is necessary here in the case where the function
1638 has both hot and cold sections, because we don't want to re-set
1639 the alignment when the section switch happens mid-function. */
1641 if (flag_reorder_blocks_and_partition)
1643 first_function_block_is_cold = false;
1645 switch_to_section (unlikely_text_section ());
1646 assemble_align (DECL_ALIGN (decl));
1647 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.cold_section_label);
1649 /* When the function starts with a cold section, we need to explicitly
1650 align the hot section and write out the hot section label.
1651 But if the current function is a thunk, we do not have a CFG. */
1652 if (!cfun->is_thunk
1653 && BB_PARTITION (ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb) == BB_COLD_PARTITION)
1655 switch_to_section (text_section);
1656 assemble_align (DECL_ALIGN (decl));
1657 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_label);
1658 hot_label_written = true;
1659 first_function_block_is_cold = true;
1661 in_cold_section_p = first_function_block_is_cold;
1665 /* Switch to the correct text section for the start of the function. */
1667 switch_to_section (function_section (decl));
1668 if (flag_reorder_blocks_and_partition
1669 && !hot_label_written)
1670 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_label);
1672 /* Tell assembler to move to target machine's alignment for functions. */
1673 align = floor_log2 (DECL_ALIGN (decl) / BITS_PER_UNIT);
1674 if (align > 0)
1676 ASM_OUTPUT_ALIGN (asm_out_file, align);
1679 /* Handle a user-specified function alignment.
1680 Note that we still need to align to DECL_ALIGN, as above,
1681 because ASM_OUTPUT_MAX_SKIP_ALIGN might not do any alignment at all. */
1682 if (! DECL_USER_ALIGN (decl)
1683 && align_functions_log > align
1684 && optimize_function_for_speed_p (cfun))
1686 #ifdef ASM_OUTPUT_MAX_SKIP_ALIGN
1687 ASM_OUTPUT_MAX_SKIP_ALIGN (asm_out_file,
1688 align_functions_log, align_functions - 1);
1689 #else
1690 ASM_OUTPUT_ALIGN (asm_out_file, align_functions_log);
1691 #endif
1694 #ifdef ASM_OUTPUT_FUNCTION_PREFIX
1695 ASM_OUTPUT_FUNCTION_PREFIX (asm_out_file, fnname);
1696 #endif
1698 if (!DECL_IGNORED_P (decl))
1699 (*debug_hooks->begin_function) (decl);
1701 /* Make function name accessible from other files, if appropriate. */
1703 if (TREE_PUBLIC (decl))
1705 notice_global_symbol (decl);
1707 globalize_decl (decl);
1709 maybe_assemble_visibility (decl);
1712 if (DECL_PRESERVE_P (decl))
1713 targetm.asm_out.mark_decl_preserved (fnname);
1715 /* Do any machine/system dependent processing of the function name. */
1716 #ifdef ASM_DECLARE_FUNCTION_NAME
1717 ASM_DECLARE_FUNCTION_NAME (asm_out_file, fnname, current_function_decl);
1718 #else
1719 /* Standard thing is just output label for the function. */
1720 ASM_OUTPUT_FUNCTION_LABEL (asm_out_file, fnname, current_function_decl);
1721 #endif /* ASM_DECLARE_FUNCTION_NAME */
1723 if (lookup_attribute ("no_split_stack", DECL_ATTRIBUTES (decl)))
1724 saw_no_split_stack = true;
1727 /* Output assembler code associated with defining the size of the
1728 function. DECL describes the function. NAME is the function's name. */
1730 void
1731 assemble_end_function (tree decl, const char *fnname ATTRIBUTE_UNUSED)
1733 #ifdef ASM_DECLARE_FUNCTION_SIZE
1734 /* We could have switched section in the middle of the function. */
1735 if (flag_reorder_blocks_and_partition)
1736 switch_to_section (function_section (decl));
1737 ASM_DECLARE_FUNCTION_SIZE (asm_out_file, fnname, decl);
1738 #endif
1739 if (! CONSTANT_POOL_BEFORE_FUNCTION)
1741 output_constant_pool (fnname, decl);
1742 switch_to_section (function_section (decl)); /* need to switch back */
1744 /* Output labels for end of hot/cold text sections (to be used by
1745 debug info.) */
1746 if (flag_reorder_blocks_and_partition)
1748 section *save_text_section;
1750 save_text_section = in_section;
1751 switch_to_section (unlikely_text_section ());
1752 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.cold_section_end_label);
1753 if (first_function_block_is_cold)
1754 switch_to_section (text_section);
1755 else
1756 switch_to_section (function_section (decl));
1757 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_end_label);
1758 switch_to_section (save_text_section);
1762 /* Assemble code to leave SIZE bytes of zeros. */
1764 void
1765 assemble_zeros (unsigned HOST_WIDE_INT size)
1767 /* Do no output if -fsyntax-only. */
1768 if (flag_syntax_only)
1769 return;
1771 #ifdef ASM_NO_SKIP_IN_TEXT
1772 /* The `space' pseudo in the text section outputs nop insns rather than 0s,
1773 so we must output 0s explicitly in the text section. */
1774 if (ASM_NO_SKIP_IN_TEXT && (in_section->common.flags & SECTION_CODE) != 0)
1776 unsigned HOST_WIDE_INT i;
1777 for (i = 0; i < size; i++)
1778 assemble_integer (const0_rtx, 1, BITS_PER_UNIT, 1);
1780 else
1781 #endif
1782 if (size > 0)
1783 ASM_OUTPUT_SKIP (asm_out_file, size);
1786 /* Assemble an alignment pseudo op for an ALIGN-bit boundary. */
1788 void
1789 assemble_align (int align)
1791 if (align > BITS_PER_UNIT)
1793 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
1797 /* Assemble a string constant with the specified C string as contents. */
1799 void
1800 assemble_string (const char *p, int size)
1802 int pos = 0;
1803 int maximum = 2000;
1805 /* If the string is very long, split it up. */
1807 while (pos < size)
1809 int thissize = size - pos;
1810 if (thissize > maximum)
1811 thissize = maximum;
1813 ASM_OUTPUT_ASCII (asm_out_file, p, thissize);
1815 pos += thissize;
1816 p += thissize;
1821 /* A noswitch_section_callback for lcomm_section. */
1823 static bool
1824 emit_local (tree decl ATTRIBUTE_UNUSED,
1825 const char *name ATTRIBUTE_UNUSED,
1826 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1827 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1829 #if defined ASM_OUTPUT_ALIGNED_DECL_LOCAL
1830 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, decl, name,
1831 size, DECL_ALIGN (decl));
1832 return true;
1833 #elif defined ASM_OUTPUT_ALIGNED_LOCAL
1834 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, DECL_ALIGN (decl));
1835 return true;
1836 #else
1837 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
1838 return false;
1839 #endif
1842 /* A noswitch_section_callback for bss_noswitch_section. */
1844 #if defined ASM_OUTPUT_ALIGNED_BSS
1845 static bool
1846 emit_bss (tree decl ATTRIBUTE_UNUSED,
1847 const char *name ATTRIBUTE_UNUSED,
1848 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1849 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1851 #if defined ASM_OUTPUT_ALIGNED_BSS
1852 ASM_OUTPUT_ALIGNED_BSS (asm_out_file, decl, name, size,
1853 get_variable_align (decl));
1854 return true;
1855 #endif
1857 #endif
1859 /* A noswitch_section_callback for comm_section. */
1861 static bool
1862 emit_common (tree decl ATTRIBUTE_UNUSED,
1863 const char *name ATTRIBUTE_UNUSED,
1864 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1865 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1867 #if defined ASM_OUTPUT_ALIGNED_DECL_COMMON
1868 ASM_OUTPUT_ALIGNED_DECL_COMMON (asm_out_file, decl, name,
1869 size, get_variable_align (decl));
1870 return true;
1871 #elif defined ASM_OUTPUT_ALIGNED_COMMON
1872 ASM_OUTPUT_ALIGNED_COMMON (asm_out_file, name, size,
1873 get_variable_align (decl));
1874 return true;
1875 #else
1876 ASM_OUTPUT_COMMON (asm_out_file, name, size, rounded);
1877 return false;
1878 #endif
1881 /* A noswitch_section_callback for tls_comm_section. */
1883 static bool
1884 emit_tls_common (tree decl ATTRIBUTE_UNUSED,
1885 const char *name ATTRIBUTE_UNUSED,
1886 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1887 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1889 #ifdef ASM_OUTPUT_TLS_COMMON
1890 ASM_OUTPUT_TLS_COMMON (asm_out_file, decl, name, size);
1891 return true;
1892 #else
1893 sorry ("thread-local COMMON data not implemented");
1894 return true;
1895 #endif
1898 /* Assemble DECL given that it belongs in SECTION_NOSWITCH section SECT.
1899 NAME is the name of DECL's SYMBOL_REF. */
1901 static void
1902 assemble_noswitch_variable (tree decl, const char *name, section *sect,
1903 unsigned int align)
1905 unsigned HOST_WIDE_INT size, rounded;
1907 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
1908 rounded = size;
1910 if ((flag_sanitize & SANITIZE_ADDRESS) && asan_protect_global (decl))
1911 size += asan_red_zone_size (size);
1913 /* Don't allocate zero bytes of common,
1914 since that means "undefined external" in the linker. */
1915 if (size == 0)
1916 rounded = 1;
1918 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
1919 so that each uninitialized object starts on such a boundary. */
1920 rounded += (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1;
1921 rounded = (rounded / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
1922 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
1924 if (!sect->noswitch.callback (decl, name, size, rounded)
1925 && (unsigned HOST_WIDE_INT) (align / BITS_PER_UNIT) > rounded)
1926 error ("requested alignment for %q+D is greater than "
1927 "implemented alignment of %wu", decl, rounded);
1930 /* A subroutine of assemble_variable. Output the label and contents of
1931 DECL, whose address is a SYMBOL_REF with name NAME. DONT_OUTPUT_DATA
1932 is as for assemble_variable. */
1934 static void
1935 assemble_variable_contents (tree decl, const char *name,
1936 bool dont_output_data)
1938 /* Do any machine/system dependent processing of the object. */
1939 #ifdef ASM_DECLARE_OBJECT_NAME
1940 last_assemble_variable_decl = decl;
1941 ASM_DECLARE_OBJECT_NAME (asm_out_file, name, decl);
1942 #else
1943 /* Standard thing is just output label for the object. */
1944 ASM_OUTPUT_LABEL (asm_out_file, name);
1945 #endif /* ASM_DECLARE_OBJECT_NAME */
1947 if (!dont_output_data)
1949 if (DECL_INITIAL (decl)
1950 && DECL_INITIAL (decl) != error_mark_node
1951 && !initializer_zerop (DECL_INITIAL (decl)))
1952 /* Output the actual data. */
1953 output_constant (DECL_INITIAL (decl),
1954 tree_to_uhwi (DECL_SIZE_UNIT (decl)),
1955 get_variable_align (decl));
1956 else
1957 /* Leave space for it. */
1958 assemble_zeros (tree_to_uhwi (DECL_SIZE_UNIT (decl)));
1962 /* Assemble everything that is needed for a variable or function declaration.
1963 Not used for automatic variables, and not used for function definitions.
1964 Should not be called for variables of incomplete structure type.
1966 TOP_LEVEL is nonzero if this variable has file scope.
1967 AT_END is nonzero if this is the special handling, at end of compilation,
1968 to define things that have had only tentative definitions.
1969 DONT_OUTPUT_DATA if nonzero means don't actually output the
1970 initial value (that will be done by the caller). */
1972 void
1973 assemble_variable (tree decl, int top_level ATTRIBUTE_UNUSED,
1974 int at_end ATTRIBUTE_UNUSED, int dont_output_data)
1976 const char *name;
1977 rtx decl_rtl, symbol;
1978 section *sect;
1979 unsigned int align;
1980 bool asan_protected = false;
1982 /* This function is supposed to handle VARIABLES. Ensure we have one. */
1983 gcc_assert (TREE_CODE (decl) == VAR_DECL);
1985 /* Emulated TLS had better not get this far. */
1986 gcc_checking_assert (targetm.have_tls || !DECL_THREAD_LOCAL_P (decl));
1988 last_assemble_variable_decl = 0;
1990 /* Normally no need to say anything here for external references,
1991 since assemble_external is called by the language-specific code
1992 when a declaration is first seen. */
1994 if (DECL_EXTERNAL (decl))
1995 return;
1997 /* Do nothing for global register variables. */
1998 if (DECL_RTL_SET_P (decl) && REG_P (DECL_RTL (decl)))
2000 TREE_ASM_WRITTEN (decl) = 1;
2001 return;
2004 /* If type was incomplete when the variable was declared,
2005 see if it is complete now. */
2007 if (DECL_SIZE (decl) == 0)
2008 layout_decl (decl, 0);
2010 /* Still incomplete => don't allocate it; treat the tentative defn
2011 (which is what it must have been) as an `extern' reference. */
2013 if (!dont_output_data && DECL_SIZE (decl) == 0)
2015 error ("storage size of %q+D isn%'t known", decl);
2016 TREE_ASM_WRITTEN (decl) = 1;
2017 return;
2020 /* The first declaration of a variable that comes through this function
2021 decides whether it is global (in C, has external linkage)
2022 or local (in C, has internal linkage). So do nothing more
2023 if this function has already run. */
2025 if (TREE_ASM_WRITTEN (decl))
2026 return;
2028 /* Make sure targetm.encode_section_info is invoked before we set
2029 ASM_WRITTEN. */
2030 decl_rtl = DECL_RTL (decl);
2032 TREE_ASM_WRITTEN (decl) = 1;
2034 /* Do no output if -fsyntax-only. */
2035 if (flag_syntax_only)
2036 return;
2038 if (! dont_output_data
2039 && ! valid_constant_size_p (DECL_SIZE_UNIT (decl)))
2041 error ("size of variable %q+D is too large", decl);
2042 return;
2045 gcc_assert (MEM_P (decl_rtl));
2046 gcc_assert (GET_CODE (XEXP (decl_rtl, 0)) == SYMBOL_REF);
2047 symbol = XEXP (decl_rtl, 0);
2049 /* If this symbol belongs to the tree constant pool, output the constant
2050 if it hasn't already been written. */
2051 if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
2053 tree decl = SYMBOL_REF_DECL (symbol);
2054 if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl)))
2055 output_constant_def_contents (symbol);
2056 return;
2059 app_disable ();
2061 name = XSTR (symbol, 0);
2062 if (TREE_PUBLIC (decl) && DECL_NAME (decl))
2063 notice_global_symbol (decl);
2065 /* Compute the alignment of this data. */
2067 align_variable (decl, dont_output_data);
2069 if ((flag_sanitize & SANITIZE_ADDRESS)
2070 && asan_protect_global (decl))
2072 asan_protected = true;
2073 DECL_ALIGN (decl) = MAX (DECL_ALIGN (decl),
2074 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
2077 set_mem_align (decl_rtl, DECL_ALIGN (decl));
2079 align = get_variable_align (decl);
2081 if (TREE_PUBLIC (decl))
2082 maybe_assemble_visibility (decl);
2084 if (DECL_PRESERVE_P (decl))
2085 targetm.asm_out.mark_decl_preserved (name);
2087 /* First make the assembler name(s) global if appropriate. */
2088 sect = get_variable_section (decl, false);
2089 if (TREE_PUBLIC (decl)
2090 && (sect->common.flags & SECTION_COMMON) == 0)
2091 globalize_decl (decl);
2093 /* Output any data that we will need to use the address of. */
2094 if (DECL_INITIAL (decl) && DECL_INITIAL (decl) != error_mark_node)
2095 output_addressed_constants (DECL_INITIAL (decl));
2097 /* dbxout.c needs to know this. */
2098 if (sect && (sect->common.flags & SECTION_CODE) != 0)
2099 DECL_IN_TEXT_SECTION (decl) = 1;
2101 /* If the decl is part of an object_block, make sure that the decl
2102 has been positioned within its block, but do not write out its
2103 definition yet. output_object_blocks will do that later. */
2104 if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol))
2106 gcc_assert (!dont_output_data);
2107 place_block_symbol (symbol);
2109 else if (SECTION_STYLE (sect) == SECTION_NOSWITCH)
2110 assemble_noswitch_variable (decl, name, sect, align);
2111 else
2113 /* The following bit of code ensures that vtable_map
2114 variables are not only in the comdat section, but that
2115 each variable has its own unique comdat name. If this
2116 code is removed, the variables end up in the same section
2117 with a single comdat name.
2119 FIXME: resolve_unique_section needs to deal better with
2120 decls with both DECL_SECTION_NAME and DECL_ONE_ONLY. Once
2121 that is fixed, this if-else statement can be replaced with
2122 a single call to "switch_to_section (sect)". */
2123 if (sect->named.name
2124 && (strcmp (sect->named.name, ".vtable_map_vars") == 0))
2126 #if defined (OBJECT_FORMAT_ELF)
2127 targetm.asm_out.named_section (sect->named.name,
2128 sect->named.common.flags
2129 | SECTION_LINKONCE,
2130 DECL_NAME (decl));
2131 in_section = sect;
2132 #else
2133 switch_to_section (sect);
2134 #endif
2136 else
2137 switch_to_section (sect);
2138 if (align > BITS_PER_UNIT)
2139 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
2140 assemble_variable_contents (decl, name, dont_output_data);
2141 if (asan_protected)
2143 unsigned HOST_WIDE_INT int size
2144 = tree_to_uhwi (DECL_SIZE_UNIT (decl));
2145 assemble_zeros (asan_red_zone_size (size));
2151 /* Given a function declaration (FN_DECL), this function assembles the
2152 function into the .preinit_array section. */
2154 void
2155 assemble_vtv_preinit_initializer (tree fn_decl)
2157 section *sect;
2158 unsigned flags = SECTION_WRITE;
2159 rtx symbol = XEXP (DECL_RTL (fn_decl), 0);
2161 flags |= SECTION_NOTYPE;
2162 sect = get_section (".preinit_array", flags, fn_decl);
2163 switch_to_section (sect);
2164 assemble_addr_to_section (symbol, sect);
2167 /* Return 1 if type TYPE contains any pointers. */
2169 static int
2170 contains_pointers_p (tree type)
2172 switch (TREE_CODE (type))
2174 case POINTER_TYPE:
2175 case REFERENCE_TYPE:
2176 /* I'm not sure whether OFFSET_TYPE needs this treatment,
2177 so I'll play safe and return 1. */
2178 case OFFSET_TYPE:
2179 return 1;
2181 case RECORD_TYPE:
2182 case UNION_TYPE:
2183 case QUAL_UNION_TYPE:
2185 tree fields;
2186 /* For a type that has fields, see if the fields have pointers. */
2187 for (fields = TYPE_FIELDS (type); fields; fields = DECL_CHAIN (fields))
2188 if (TREE_CODE (fields) == FIELD_DECL
2189 && contains_pointers_p (TREE_TYPE (fields)))
2190 return 1;
2191 return 0;
2194 case ARRAY_TYPE:
2195 /* An array type contains pointers if its element type does. */
2196 return contains_pointers_p (TREE_TYPE (type));
2198 default:
2199 return 0;
2203 /* We delay assemble_external processing until
2204 the compilation unit is finalized. This is the best we can do for
2205 right now (i.e. stage 3 of GCC 4.0) - the right thing is to delay
2206 it all the way to final. See PR 17982 for further discussion. */
2207 static GTY(()) tree pending_assemble_externals;
2209 #ifdef ASM_OUTPUT_EXTERNAL
2210 /* Some targets delay some output to final using TARGET_ASM_FILE_END.
2211 As a result, assemble_external can be called after the list of externals
2212 is processed and the pointer set destroyed. */
2213 static bool pending_assemble_externals_processed;
2215 /* Avoid O(external_decls**2) lookups in the pending_assemble_externals
2216 TREE_LIST in assemble_external. */
2217 static struct pointer_set_t *pending_assemble_externals_set;
2219 /* True if DECL is a function decl for which no out-of-line copy exists.
2220 It is assumed that DECL's assembler name has been set. */
2222 static bool
2223 incorporeal_function_p (tree decl)
2225 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_BUILT_IN (decl))
2227 const char *name;
2229 if (DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL
2230 && (DECL_FUNCTION_CODE (decl) == BUILT_IN_ALLOCA
2231 || DECL_FUNCTION_CODE (decl) == BUILT_IN_ALLOCA_WITH_ALIGN))
2232 return true;
2234 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
2235 /* Atomic or sync builtins which have survived this far will be
2236 resolved externally and therefore are not incorporeal. */
2237 if (strncmp (name, "__builtin_", 10) == 0)
2238 return true;
2240 return false;
2243 /* Actually do the tests to determine if this is necessary, and invoke
2244 ASM_OUTPUT_EXTERNAL. */
2245 static void
2246 assemble_external_real (tree decl)
2248 rtx rtl = DECL_RTL (decl);
2250 if (MEM_P (rtl) && GET_CODE (XEXP (rtl, 0)) == SYMBOL_REF
2251 && !SYMBOL_REF_USED (XEXP (rtl, 0))
2252 && !incorporeal_function_p (decl))
2254 /* Some systems do require some output. */
2255 SYMBOL_REF_USED (XEXP (rtl, 0)) = 1;
2256 ASM_OUTPUT_EXTERNAL (asm_out_file, decl, XSTR (XEXP (rtl, 0), 0));
2259 #endif
2261 void
2262 process_pending_assemble_externals (void)
2264 #ifdef ASM_OUTPUT_EXTERNAL
2265 tree list;
2266 for (list = pending_assemble_externals; list; list = TREE_CHAIN (list))
2267 assemble_external_real (TREE_VALUE (list));
2269 pending_assemble_externals = 0;
2270 pending_assemble_externals_processed = true;
2271 pointer_set_destroy (pending_assemble_externals_set);
2272 #endif
2275 /* This TREE_LIST contains any weak symbol declarations waiting
2276 to be emitted. */
2277 static GTY(()) tree weak_decls;
2279 /* Output something to declare an external symbol to the assembler,
2280 and qualifiers such as weakness. (Most assemblers don't need
2281 extern declaration, so we normally output nothing.) Do nothing if
2282 DECL is not external. */
2284 void
2285 assemble_external (tree decl ATTRIBUTE_UNUSED)
2287 /* Make sure that the ASM_OUT_FILE is open.
2288 If it's not, we should not be calling this function. */
2289 gcc_assert (asm_out_file);
2291 /* In a perfect world, the following condition would be true.
2292 Sadly, the Java and Go front ends emit assembly *from the front end*,
2293 bypassing the call graph. See PR52739. Fix before GCC 4.8. */
2294 #if 0
2295 /* This function should only be called if we are expanding, or have
2296 expanded, to RTL.
2297 Ideally, only final.c would be calling this function, but it is
2298 not clear whether that would break things somehow. See PR 17982
2299 for further discussion. */
2300 gcc_assert (cgraph_state == CGRAPH_STATE_EXPANSION
2301 || cgraph_state == CGRAPH_STATE_FINISHED);
2302 #endif
2304 if (!DECL_P (decl) || !DECL_EXTERNAL (decl) || !TREE_PUBLIC (decl))
2305 return;
2307 /* We want to output annotation for weak and external symbols at
2308 very last to check if they are references or not. */
2310 if (TARGET_SUPPORTS_WEAK
2311 && DECL_WEAK (decl)
2312 /* TREE_STATIC is a weird and abused creature which is not
2313 generally the right test for whether an entity has been
2314 locally emitted, inlined or otherwise not-really-extern, but
2315 for declarations that can be weak, it happens to be
2316 match. */
2317 && !TREE_STATIC (decl)
2318 && lookup_attribute ("weak", DECL_ATTRIBUTES (decl))
2319 && value_member (decl, weak_decls) == NULL_TREE)
2320 weak_decls = tree_cons (NULL, decl, weak_decls);
2322 #ifdef ASM_OUTPUT_EXTERNAL
2323 if (pending_assemble_externals_processed)
2325 assemble_external_real (decl);
2326 return;
2329 if (! pointer_set_insert (pending_assemble_externals_set, decl))
2330 pending_assemble_externals = tree_cons (NULL, decl,
2331 pending_assemble_externals);
2332 #endif
2335 /* Similar, for calling a library function FUN. */
2337 void
2338 assemble_external_libcall (rtx fun)
2340 /* Declare library function name external when first used, if nec. */
2341 if (! SYMBOL_REF_USED (fun))
2343 SYMBOL_REF_USED (fun) = 1;
2344 targetm.asm_out.external_libcall (fun);
2348 /* Assemble a label named NAME. */
2350 void
2351 assemble_label (FILE *file, const char *name)
2353 ASM_OUTPUT_LABEL (file, name);
2356 /* Set the symbol_referenced flag for ID. */
2357 void
2358 mark_referenced (tree id)
2360 TREE_SYMBOL_REFERENCED (id) = 1;
2363 /* Set the symbol_referenced flag for DECL and notify callgraph. */
2364 void
2365 mark_decl_referenced (tree decl)
2367 if (TREE_CODE (decl) == FUNCTION_DECL)
2369 /* Extern inline functions don't become needed when referenced.
2370 If we know a method will be emitted in other TU and no new
2371 functions can be marked reachable, just use the external
2372 definition. */
2373 struct cgraph_node *node = cgraph_get_create_node (decl);
2374 if (!DECL_EXTERNAL (decl)
2375 && !node->definition)
2376 cgraph_mark_force_output_node (node);
2378 else if (TREE_CODE (decl) == VAR_DECL)
2380 varpool_node *node = varpool_node_for_decl (decl);
2381 /* C++ frontend use mark_decl_references to force COMDAT variables
2382 to be output that might appear dead otherwise. */
2383 node->force_output = true;
2385 /* else do nothing - we can get various sorts of CST nodes here,
2386 which do not need to be marked. */
2390 /* Follow the IDENTIFIER_TRANSPARENT_ALIAS chain starting at *ALIAS
2391 until we find an identifier that is not itself a transparent alias.
2392 Modify the alias passed to it by reference (and all aliases on the
2393 way to the ultimate target), such that they do not have to be
2394 followed again, and return the ultimate target of the alias
2395 chain. */
2397 static inline tree
2398 ultimate_transparent_alias_target (tree *alias)
2400 tree target = *alias;
2402 if (IDENTIFIER_TRANSPARENT_ALIAS (target))
2404 gcc_assert (TREE_CHAIN (target));
2405 target = ultimate_transparent_alias_target (&TREE_CHAIN (target));
2406 gcc_assert (! IDENTIFIER_TRANSPARENT_ALIAS (target)
2407 && ! TREE_CHAIN (target));
2408 *alias = target;
2411 return target;
2414 /* Output to FILE (an assembly file) a reference to NAME. If NAME
2415 starts with a *, the rest of NAME is output verbatim. Otherwise
2416 NAME is transformed in a target-specific way (usually by the
2417 addition of an underscore). */
2419 void
2420 assemble_name_raw (FILE *file, const char *name)
2422 if (name[0] == '*')
2423 fputs (&name[1], file);
2424 else
2425 ASM_OUTPUT_LABELREF (file, name);
2428 /* Like assemble_name_raw, but should be used when NAME might refer to
2429 an entity that is also represented as a tree (like a function or
2430 variable). If NAME does refer to such an entity, that entity will
2431 be marked as referenced. */
2433 void
2434 assemble_name (FILE *file, const char *name)
2436 const char *real_name;
2437 tree id;
2439 real_name = targetm.strip_name_encoding (name);
2441 id = maybe_get_identifier (real_name);
2442 if (id)
2444 tree id_orig = id;
2446 mark_referenced (id);
2447 ultimate_transparent_alias_target (&id);
2448 if (id != id_orig)
2449 name = IDENTIFIER_POINTER (id);
2450 gcc_assert (! TREE_CHAIN (id));
2453 assemble_name_raw (file, name);
2456 /* Allocate SIZE bytes writable static space with a gensym name
2457 and return an RTX to refer to its address. */
2460 assemble_static_space (unsigned HOST_WIDE_INT size)
2462 char name[12];
2463 const char *namestring;
2464 rtx x;
2466 ASM_GENERATE_INTERNAL_LABEL (name, "LF", const_labelno);
2467 ++const_labelno;
2468 namestring = ggc_strdup (name);
2470 x = gen_rtx_SYMBOL_REF (Pmode, namestring);
2471 SYMBOL_REF_FLAGS (x) = SYMBOL_FLAG_LOCAL;
2473 #ifdef ASM_OUTPUT_ALIGNED_DECL_LOCAL
2474 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, NULL_TREE, name, size,
2475 BIGGEST_ALIGNMENT);
2476 #else
2477 #ifdef ASM_OUTPUT_ALIGNED_LOCAL
2478 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, BIGGEST_ALIGNMENT);
2479 #else
2481 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
2482 so that each uninitialized object starts on such a boundary. */
2483 /* Variable `rounded' might or might not be used in ASM_OUTPUT_LOCAL. */
2484 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED
2485 = ((size + (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1)
2486 / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
2487 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
2488 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
2490 #endif
2491 #endif
2492 return x;
2495 /* Assemble the static constant template for function entry trampolines.
2496 This is done at most once per compilation.
2497 Returns an RTX for the address of the template. */
2499 static GTY(()) rtx initial_trampoline;
2502 assemble_trampoline_template (void)
2504 char label[256];
2505 const char *name;
2506 int align;
2507 rtx symbol;
2509 gcc_assert (targetm.asm_out.trampoline_template != NULL);
2511 if (initial_trampoline)
2512 return initial_trampoline;
2514 /* By default, put trampoline templates in read-only data section. */
2516 #ifdef TRAMPOLINE_SECTION
2517 switch_to_section (TRAMPOLINE_SECTION);
2518 #else
2519 switch_to_section (readonly_data_section);
2520 #endif
2522 /* Write the assembler code to define one. */
2523 align = floor_log2 (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
2524 if (align > 0)
2525 ASM_OUTPUT_ALIGN (asm_out_file, align);
2527 targetm.asm_out.internal_label (asm_out_file, "LTRAMP", 0);
2528 targetm.asm_out.trampoline_template (asm_out_file);
2530 /* Record the rtl to refer to it. */
2531 ASM_GENERATE_INTERNAL_LABEL (label, "LTRAMP", 0);
2532 name = ggc_strdup (label);
2533 symbol = gen_rtx_SYMBOL_REF (Pmode, name);
2534 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_LOCAL;
2536 initial_trampoline = gen_const_mem (BLKmode, symbol);
2537 set_mem_align (initial_trampoline, TRAMPOLINE_ALIGNMENT);
2538 set_mem_size (initial_trampoline, TRAMPOLINE_SIZE);
2540 return initial_trampoline;
2543 /* A and B are either alignments or offsets. Return the minimum alignment
2544 that may be assumed after adding the two together. */
2546 static inline unsigned
2547 min_align (unsigned int a, unsigned int b)
2549 return (a | b) & -(a | b);
2552 /* Return the assembler directive for creating a given kind of integer
2553 object. SIZE is the number of bytes in the object and ALIGNED_P
2554 indicates whether it is known to be aligned. Return NULL if the
2555 assembly dialect has no such directive.
2557 The returned string should be printed at the start of a new line and
2558 be followed immediately by the object's initial value. */
2560 const char *
2561 integer_asm_op (int size, int aligned_p)
2563 struct asm_int_op *ops;
2565 if (aligned_p)
2566 ops = &targetm.asm_out.aligned_op;
2567 else
2568 ops = &targetm.asm_out.unaligned_op;
2570 switch (size)
2572 case 1:
2573 return targetm.asm_out.byte_op;
2574 case 2:
2575 return ops->hi;
2576 case 4:
2577 return ops->si;
2578 case 8:
2579 return ops->di;
2580 case 16:
2581 return ops->ti;
2582 default:
2583 return NULL;
2587 /* Use directive OP to assemble an integer object X. Print OP at the
2588 start of the line, followed immediately by the value of X. */
2590 void
2591 assemble_integer_with_op (const char *op, rtx x)
2593 fputs (op, asm_out_file);
2594 output_addr_const (asm_out_file, x);
2595 fputc ('\n', asm_out_file);
2598 /* The default implementation of the asm_out.integer target hook. */
2600 bool
2601 default_assemble_integer (rtx x ATTRIBUTE_UNUSED,
2602 unsigned int size ATTRIBUTE_UNUSED,
2603 int aligned_p ATTRIBUTE_UNUSED)
2605 const char *op = integer_asm_op (size, aligned_p);
2606 /* Avoid GAS bugs for large values. Specifically negative values whose
2607 absolute value fits in a bfd_vma, but not in a bfd_signed_vma. */
2608 if (size > UNITS_PER_WORD && size > POINTER_SIZE / BITS_PER_UNIT)
2609 return false;
2610 return op && (assemble_integer_with_op (op, x), true);
2613 /* Assemble the integer constant X into an object of SIZE bytes. ALIGN is
2614 the alignment of the integer in bits. Return 1 if we were able to output
2615 the constant, otherwise 0. We must be able to output the constant,
2616 if FORCE is nonzero. */
2618 bool
2619 assemble_integer (rtx x, unsigned int size, unsigned int align, int force)
2621 int aligned_p;
2623 aligned_p = (align >= MIN (size * BITS_PER_UNIT, BIGGEST_ALIGNMENT));
2625 /* See if the target hook can handle this kind of object. */
2626 if (targetm.asm_out.integer (x, size, aligned_p))
2627 return true;
2629 /* If the object is a multi-byte one, try splitting it up. Split
2630 it into words it if is multi-word, otherwise split it into bytes. */
2631 if (size > 1)
2633 enum machine_mode omode, imode;
2634 unsigned int subalign;
2635 unsigned int subsize, i;
2636 enum mode_class mclass;
2638 subsize = size > UNITS_PER_WORD? UNITS_PER_WORD : 1;
2639 subalign = MIN (align, subsize * BITS_PER_UNIT);
2640 if (GET_CODE (x) == CONST_FIXED)
2641 mclass = GET_MODE_CLASS (GET_MODE (x));
2642 else
2643 mclass = MODE_INT;
2645 omode = mode_for_size (subsize * BITS_PER_UNIT, mclass, 0);
2646 imode = mode_for_size (size * BITS_PER_UNIT, mclass, 0);
2648 for (i = 0; i < size; i += subsize)
2650 rtx partial = simplify_subreg (omode, x, imode, i);
2651 if (!partial || !assemble_integer (partial, subsize, subalign, 0))
2652 break;
2654 if (i == size)
2655 return true;
2657 /* If we've printed some of it, but not all of it, there's no going
2658 back now. */
2659 gcc_assert (!i);
2662 gcc_assert (!force);
2664 return false;
2667 void
2668 assemble_real (REAL_VALUE_TYPE d, enum machine_mode mode, unsigned int align)
2670 long data[4] = {0, 0, 0, 0};
2671 int i;
2672 int bitsize, nelts, nunits, units_per;
2674 /* This is hairy. We have a quantity of known size. real_to_target
2675 will put it into an array of *host* longs, 32 bits per element
2676 (even if long is more than 32 bits). We need to determine the
2677 number of array elements that are occupied (nelts) and the number
2678 of *target* min-addressable units that will be occupied in the
2679 object file (nunits). We cannot assume that 32 divides the
2680 mode's bitsize (size * BITS_PER_UNIT) evenly.
2682 size * BITS_PER_UNIT is used here to make sure that padding bits
2683 (which might appear at either end of the value; real_to_target
2684 will include the padding bits in its output array) are included. */
2686 nunits = GET_MODE_SIZE (mode);
2687 bitsize = nunits * BITS_PER_UNIT;
2688 nelts = CEIL (bitsize, 32);
2689 units_per = 32 / BITS_PER_UNIT;
2691 real_to_target (data, &d, mode);
2693 /* Put out the first word with the specified alignment. */
2694 assemble_integer (GEN_INT (data[0]), MIN (nunits, units_per), align, 1);
2695 nunits -= units_per;
2697 /* Subsequent words need only 32-bit alignment. */
2698 align = min_align (align, 32);
2700 for (i = 1; i < nelts; i++)
2702 assemble_integer (GEN_INT (data[i]), MIN (nunits, units_per), align, 1);
2703 nunits -= units_per;
2707 /* Given an expression EXP with a constant value,
2708 reduce it to the sum of an assembler symbol and an integer.
2709 Store them both in the structure *VALUE.
2710 EXP must be reducible. */
2712 struct addr_const {
2713 rtx base;
2714 HOST_WIDE_INT offset;
2717 static void
2718 decode_addr_const (tree exp, struct addr_const *value)
2720 tree target = TREE_OPERAND (exp, 0);
2721 int offset = 0;
2722 rtx x;
2724 while (1)
2726 if (TREE_CODE (target) == COMPONENT_REF
2727 && tree_fits_shwi_p (byte_position (TREE_OPERAND (target, 1))))
2729 offset += int_byte_position (TREE_OPERAND (target, 1));
2730 target = TREE_OPERAND (target, 0);
2732 else if (TREE_CODE (target) == ARRAY_REF
2733 || TREE_CODE (target) == ARRAY_RANGE_REF)
2735 offset += (tree_to_uhwi (TYPE_SIZE_UNIT (TREE_TYPE (target)))
2736 * tree_to_shwi (TREE_OPERAND (target, 1)));
2737 target = TREE_OPERAND (target, 0);
2739 else if (TREE_CODE (target) == MEM_REF
2740 && TREE_CODE (TREE_OPERAND (target, 0)) == ADDR_EXPR)
2742 offset += mem_ref_offset (target).to_short_addr ();
2743 target = TREE_OPERAND (TREE_OPERAND (target, 0), 0);
2745 else if (TREE_CODE (target) == INDIRECT_REF
2746 && TREE_CODE (TREE_OPERAND (target, 0)) == NOP_EXPR
2747 && TREE_CODE (TREE_OPERAND (TREE_OPERAND (target, 0), 0))
2748 == ADDR_EXPR)
2749 target = TREE_OPERAND (TREE_OPERAND (TREE_OPERAND (target, 0), 0), 0);
2750 else
2751 break;
2754 switch (TREE_CODE (target))
2756 case VAR_DECL:
2757 case FUNCTION_DECL:
2758 x = DECL_RTL (target);
2759 break;
2761 case LABEL_DECL:
2762 x = gen_rtx_MEM (FUNCTION_MODE,
2763 gen_rtx_LABEL_REF (Pmode, force_label_rtx (target)));
2764 break;
2766 case REAL_CST:
2767 case FIXED_CST:
2768 case STRING_CST:
2769 case COMPLEX_CST:
2770 case CONSTRUCTOR:
2771 case INTEGER_CST:
2772 x = output_constant_def (target, 1);
2773 break;
2775 default:
2776 gcc_unreachable ();
2779 gcc_assert (MEM_P (x));
2780 x = XEXP (x, 0);
2782 value->base = x;
2783 value->offset = offset;
2787 static GTY((param_is (struct constant_descriptor_tree)))
2788 htab_t const_desc_htab;
2790 static void maybe_output_constant_def_contents (struct constant_descriptor_tree *, int);
2792 /* Constant pool accessor function. */
2794 htab_t
2795 constant_pool_htab (void)
2797 return const_desc_htab;
2800 /* Compute a hash code for a constant expression. */
2802 static hashval_t
2803 const_desc_hash (const void *ptr)
2805 return ((const struct constant_descriptor_tree *)ptr)->hash;
2808 static hashval_t
2809 const_hash_1 (const tree exp)
2811 const char *p;
2812 hashval_t hi;
2813 int len, i;
2814 enum tree_code code = TREE_CODE (exp);
2816 /* Either set P and LEN to the address and len of something to hash and
2817 exit the switch or return a value. */
2819 switch (code)
2821 case INTEGER_CST:
2822 p = (char *) &TREE_INT_CST_ELT (exp, 0);
2823 len = TREE_INT_CST_NUNITS (exp) * sizeof (HOST_WIDE_INT);
2824 break;
2826 case REAL_CST:
2827 return real_hash (TREE_REAL_CST_PTR (exp));
2829 case FIXED_CST:
2830 return fixed_hash (TREE_FIXED_CST_PTR (exp));
2832 case STRING_CST:
2833 p = TREE_STRING_POINTER (exp);
2834 len = TREE_STRING_LENGTH (exp);
2835 break;
2837 case COMPLEX_CST:
2838 return (const_hash_1 (TREE_REALPART (exp)) * 5
2839 + const_hash_1 (TREE_IMAGPART (exp)));
2841 case VECTOR_CST:
2843 unsigned i;
2845 hi = 7 + VECTOR_CST_NELTS (exp);
2847 for (i = 0; i < VECTOR_CST_NELTS (exp); ++i)
2848 hi = hi * 563 + const_hash_1 (VECTOR_CST_ELT (exp, i));
2850 return hi;
2853 case CONSTRUCTOR:
2855 unsigned HOST_WIDE_INT idx;
2856 tree value;
2858 hi = 5 + int_size_in_bytes (TREE_TYPE (exp));
2860 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, value)
2861 if (value)
2862 hi = hi * 603 + const_hash_1 (value);
2864 return hi;
2867 case ADDR_EXPR:
2868 case FDESC_EXPR:
2870 struct addr_const value;
2872 decode_addr_const (exp, &value);
2873 switch (GET_CODE (value.base))
2875 case SYMBOL_REF:
2876 /* Don't hash the address of the SYMBOL_REF;
2877 only use the offset and the symbol name. */
2878 hi = value.offset;
2879 p = XSTR (value.base, 0);
2880 for (i = 0; p[i] != 0; i++)
2881 hi = ((hi * 613) + (unsigned) (p[i]));
2882 break;
2884 case LABEL_REF:
2885 hi = value.offset + CODE_LABEL_NUMBER (XEXP (value.base, 0)) * 13;
2886 break;
2888 default:
2889 gcc_unreachable ();
2892 return hi;
2894 case PLUS_EXPR:
2895 case POINTER_PLUS_EXPR:
2896 case MINUS_EXPR:
2897 return (const_hash_1 (TREE_OPERAND (exp, 0)) * 9
2898 + const_hash_1 (TREE_OPERAND (exp, 1)));
2900 CASE_CONVERT:
2901 return const_hash_1 (TREE_OPERAND (exp, 0)) * 7 + 2;
2903 default:
2904 /* A language specific constant. Just hash the code. */
2905 return code;
2908 /* Compute hashing function. */
2909 hi = len;
2910 for (i = 0; i < len; i++)
2911 hi = ((hi * 613) + (unsigned) (p[i]));
2913 return hi;
2916 /* Wrapper of compare_constant, for the htab interface. */
2917 static int
2918 const_desc_eq (const void *p1, const void *p2)
2920 const struct constant_descriptor_tree *const c1
2921 = (const struct constant_descriptor_tree *) p1;
2922 const struct constant_descriptor_tree *const c2
2923 = (const struct constant_descriptor_tree *) p2;
2924 if (c1->hash != c2->hash)
2925 return 0;
2926 return compare_constant (c1->value, c2->value);
2929 /* Compare t1 and t2, and return 1 only if they are known to result in
2930 the same bit pattern on output. */
2932 static int
2933 compare_constant (const tree t1, const tree t2)
2935 enum tree_code typecode;
2937 if (t1 == NULL_TREE)
2938 return t2 == NULL_TREE;
2939 if (t2 == NULL_TREE)
2940 return 0;
2942 if (TREE_CODE (t1) != TREE_CODE (t2))
2943 return 0;
2945 switch (TREE_CODE (t1))
2947 case INTEGER_CST:
2948 /* Integer constants are the same only if the same width of type. */
2949 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2950 return 0;
2951 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
2952 return 0;
2953 return tree_int_cst_equal (t1, t2);
2955 case REAL_CST:
2956 /* Real constants are the same only if the same width of type. */
2957 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2958 return 0;
2960 return REAL_VALUES_IDENTICAL (TREE_REAL_CST (t1), TREE_REAL_CST (t2));
2962 case FIXED_CST:
2963 /* Fixed constants are the same only if the same width of type. */
2964 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2965 return 0;
2967 return FIXED_VALUES_IDENTICAL (TREE_FIXED_CST (t1), TREE_FIXED_CST (t2));
2969 case STRING_CST:
2970 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
2971 return 0;
2973 return (TREE_STRING_LENGTH (t1) == TREE_STRING_LENGTH (t2)
2974 && ! memcmp (TREE_STRING_POINTER (t1), TREE_STRING_POINTER (t2),
2975 TREE_STRING_LENGTH (t1)));
2977 case COMPLEX_CST:
2978 return (compare_constant (TREE_REALPART (t1), TREE_REALPART (t2))
2979 && compare_constant (TREE_IMAGPART (t1), TREE_IMAGPART (t2)));
2981 case VECTOR_CST:
2983 unsigned i;
2985 if (VECTOR_CST_NELTS (t1) != VECTOR_CST_NELTS (t2))
2986 return 0;
2988 for (i = 0; i < VECTOR_CST_NELTS (t1); ++i)
2989 if (!compare_constant (VECTOR_CST_ELT (t1, i),
2990 VECTOR_CST_ELT (t2, i)))
2991 return 0;
2993 return 1;
2996 case CONSTRUCTOR:
2998 vec<constructor_elt, va_gc> *v1, *v2;
2999 unsigned HOST_WIDE_INT idx;
3001 typecode = TREE_CODE (TREE_TYPE (t1));
3002 if (typecode != TREE_CODE (TREE_TYPE (t2)))
3003 return 0;
3005 if (typecode == ARRAY_TYPE)
3007 HOST_WIDE_INT size_1 = int_size_in_bytes (TREE_TYPE (t1));
3008 /* For arrays, check that the sizes all match. */
3009 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2))
3010 || size_1 == -1
3011 || size_1 != int_size_in_bytes (TREE_TYPE (t2)))
3012 return 0;
3014 else
3016 /* For record and union constructors, require exact type
3017 equality. */
3018 if (TREE_TYPE (t1) != TREE_TYPE (t2))
3019 return 0;
3022 v1 = CONSTRUCTOR_ELTS (t1);
3023 v2 = CONSTRUCTOR_ELTS (t2);
3024 if (vec_safe_length (v1) != vec_safe_length (v2))
3025 return 0;
3027 for (idx = 0; idx < vec_safe_length (v1); ++idx)
3029 constructor_elt *c1 = &(*v1)[idx];
3030 constructor_elt *c2 = &(*v2)[idx];
3032 /* Check that each value is the same... */
3033 if (!compare_constant (c1->value, c2->value))
3034 return 0;
3035 /* ... and that they apply to the same fields! */
3036 if (typecode == ARRAY_TYPE)
3038 if (!compare_constant (c1->index, c2->index))
3039 return 0;
3041 else
3043 if (c1->index != c2->index)
3044 return 0;
3048 return 1;
3051 case ADDR_EXPR:
3052 case FDESC_EXPR:
3054 struct addr_const value1, value2;
3055 enum rtx_code code;
3056 int ret;
3058 decode_addr_const (t1, &value1);
3059 decode_addr_const (t2, &value2);
3061 if (value1.offset != value2.offset)
3062 return 0;
3064 code = GET_CODE (value1.base);
3065 if (code != GET_CODE (value2.base))
3066 return 0;
3068 switch (code)
3070 case SYMBOL_REF:
3071 ret = (strcmp (XSTR (value1.base, 0), XSTR (value2.base, 0)) == 0);
3072 break;
3074 case LABEL_REF:
3075 ret = (CODE_LABEL_NUMBER (XEXP (value1.base, 0))
3076 == CODE_LABEL_NUMBER (XEXP (value2.base, 0)));
3077 break;
3079 default:
3080 gcc_unreachable ();
3082 return ret;
3085 case PLUS_EXPR:
3086 case POINTER_PLUS_EXPR:
3087 case MINUS_EXPR:
3088 case RANGE_EXPR:
3089 return (compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0))
3090 && compare_constant (TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1)));
3092 CASE_CONVERT:
3093 case VIEW_CONVERT_EXPR:
3094 return compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3096 default:
3097 return 0;
3100 gcc_unreachable ();
3103 /* Make a copy of the whole tree structure for a constant. This
3104 handles the same types of nodes that compare_constant handles. */
3106 static tree
3107 copy_constant (tree exp)
3109 switch (TREE_CODE (exp))
3111 case ADDR_EXPR:
3112 /* For ADDR_EXPR, we do not want to copy the decl whose address
3113 is requested. We do want to copy constants though. */
3114 if (CONSTANT_CLASS_P (TREE_OPERAND (exp, 0)))
3115 return build1 (TREE_CODE (exp), TREE_TYPE (exp),
3116 copy_constant (TREE_OPERAND (exp, 0)));
3117 else
3118 return copy_node (exp);
3120 case INTEGER_CST:
3121 case REAL_CST:
3122 case FIXED_CST:
3123 case STRING_CST:
3124 return copy_node (exp);
3126 case COMPLEX_CST:
3127 return build_complex (TREE_TYPE (exp),
3128 copy_constant (TREE_REALPART (exp)),
3129 copy_constant (TREE_IMAGPART (exp)));
3131 case PLUS_EXPR:
3132 case POINTER_PLUS_EXPR:
3133 case MINUS_EXPR:
3134 return build2 (TREE_CODE (exp), TREE_TYPE (exp),
3135 copy_constant (TREE_OPERAND (exp, 0)),
3136 copy_constant (TREE_OPERAND (exp, 1)));
3138 CASE_CONVERT:
3139 case VIEW_CONVERT_EXPR:
3140 return build1 (TREE_CODE (exp), TREE_TYPE (exp),
3141 copy_constant (TREE_OPERAND (exp, 0)));
3143 case VECTOR_CST:
3144 return build_vector (TREE_TYPE (exp), VECTOR_CST_ELTS (exp));
3146 case CONSTRUCTOR:
3148 tree copy = copy_node (exp);
3149 vec<constructor_elt, va_gc> *v;
3150 unsigned HOST_WIDE_INT idx;
3151 tree purpose, value;
3153 vec_alloc (v, vec_safe_length (CONSTRUCTOR_ELTS (exp)));
3154 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (exp), idx, purpose, value)
3156 constructor_elt ce = {purpose, copy_constant (value)};
3157 v->quick_push (ce);
3159 CONSTRUCTOR_ELTS (copy) = v;
3160 return copy;
3163 default:
3164 gcc_unreachable ();
3168 /* Return the section into which constant EXP should be placed. */
3170 static section *
3171 get_constant_section (tree exp, unsigned int align)
3173 return targetm.asm_out.select_section (exp,
3174 compute_reloc_for_constant (exp),
3175 align);
3178 /* Return the size of constant EXP in bytes. */
3180 static HOST_WIDE_INT
3181 get_constant_size (tree exp)
3183 HOST_WIDE_INT size;
3185 size = int_size_in_bytes (TREE_TYPE (exp));
3186 if (TREE_CODE (exp) == STRING_CST)
3187 size = MAX (TREE_STRING_LENGTH (exp), size);
3188 return size;
3191 /* Subroutine of output_constant_def:
3192 No constant equal to EXP is known to have been output.
3193 Make a constant descriptor to enter EXP in the hash table.
3194 Assign the label number and construct RTL to refer to the
3195 constant's location in memory.
3196 Caller is responsible for updating the hash table. */
3198 static struct constant_descriptor_tree *
3199 build_constant_desc (tree exp)
3201 struct constant_descriptor_tree *desc;
3202 rtx symbol, rtl;
3203 char label[256];
3204 int labelno;
3205 tree decl;
3207 desc = ggc_alloc<constant_descriptor_tree> ();
3208 desc->value = copy_constant (exp);
3210 /* Create a string containing the label name, in LABEL. */
3211 labelno = const_labelno++;
3212 ASM_GENERATE_INTERNAL_LABEL (label, "LC", labelno);
3214 /* Construct the VAR_DECL associated with the constant. */
3215 decl = build_decl (UNKNOWN_LOCATION, VAR_DECL, get_identifier (label),
3216 TREE_TYPE (exp));
3217 DECL_ARTIFICIAL (decl) = 1;
3218 DECL_IGNORED_P (decl) = 1;
3219 TREE_READONLY (decl) = 1;
3220 TREE_STATIC (decl) = 1;
3221 TREE_ADDRESSABLE (decl) = 1;
3222 /* We don't set the RTL yet as this would cause varpool to assume that the
3223 variable is referenced. Moreover, it would just be dropped in LTO mode.
3224 Instead we set the flag that will be recognized in make_decl_rtl. */
3225 DECL_IN_CONSTANT_POOL (decl) = 1;
3226 DECL_INITIAL (decl) = desc->value;
3227 /* ??? CONSTANT_ALIGNMENT hasn't been updated for vector types on most
3228 architectures so use DATA_ALIGNMENT as well, except for strings. */
3229 if (TREE_CODE (exp) == STRING_CST)
3231 #ifdef CONSTANT_ALIGNMENT
3232 DECL_ALIGN (decl) = CONSTANT_ALIGNMENT (exp, DECL_ALIGN (decl));
3233 #endif
3235 else
3236 align_variable (decl, 0);
3238 /* Now construct the SYMBOL_REF and the MEM. */
3239 if (use_object_blocks_p ())
3241 section *sect = get_constant_section (exp, DECL_ALIGN (decl));
3242 symbol = create_block_symbol (ggc_strdup (label),
3243 get_block_for_section (sect), -1);
3245 else
3246 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3247 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3248 SET_SYMBOL_REF_DECL (symbol, decl);
3249 TREE_CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3251 rtl = gen_const_mem (TYPE_MODE (TREE_TYPE (exp)), symbol);
3252 set_mem_attributes (rtl, exp, 1);
3253 set_mem_alias_set (rtl, 0);
3254 set_mem_alias_set (rtl, const_alias_set);
3256 /* We cannot share RTX'es in pool entries.
3257 Mark this piece of RTL as required for unsharing. */
3258 RTX_FLAG (rtl, used) = 1;
3260 /* Set flags or add text to the name to record information, such as
3261 that it is a local symbol. If the name is changed, the macro
3262 ASM_OUTPUT_LABELREF will have to know how to strip this
3263 information. This call might invalidate our local variable
3264 SYMBOL; we can't use it afterward. */
3265 targetm.encode_section_info (exp, rtl, true);
3267 desc->rtl = rtl;
3269 return desc;
3272 /* Return an rtx representing a reference to constant data in memory
3273 for the constant expression EXP.
3275 If assembler code for such a constant has already been output,
3276 return an rtx to refer to it.
3277 Otherwise, output such a constant in memory
3278 and generate an rtx for it.
3280 If DEFER is nonzero, this constant can be deferred and output only
3281 if referenced in the function after all optimizations.
3283 `const_desc_table' records which constants already have label strings. */
3286 output_constant_def (tree exp, int defer)
3288 struct constant_descriptor_tree *desc;
3289 struct constant_descriptor_tree key;
3290 void **loc;
3292 /* Look up EXP in the table of constant descriptors. If we didn't find
3293 it, create a new one. */
3294 key.value = exp;
3295 key.hash = const_hash_1 (exp);
3296 loc = htab_find_slot_with_hash (const_desc_htab, &key, key.hash, INSERT);
3298 desc = (struct constant_descriptor_tree *) *loc;
3299 if (desc == 0)
3301 desc = build_constant_desc (exp);
3302 desc->hash = key.hash;
3303 *loc = desc;
3306 maybe_output_constant_def_contents (desc, defer);
3307 return desc->rtl;
3310 /* Subroutine of output_constant_def: Decide whether or not we need to
3311 output the constant DESC now, and if so, do it. */
3312 static void
3313 maybe_output_constant_def_contents (struct constant_descriptor_tree *desc,
3314 int defer)
3316 rtx symbol = XEXP (desc->rtl, 0);
3317 tree exp = desc->value;
3319 if (flag_syntax_only)
3320 return;
3322 if (TREE_ASM_WRITTEN (exp))
3323 /* Already output; don't do it again. */
3324 return;
3326 /* We can always defer constants as long as the context allows
3327 doing so. */
3328 if (defer)
3330 /* Increment n_deferred_constants if it exists. It needs to be at
3331 least as large as the number of constants actually referred to
3332 by the function. If it's too small we'll stop looking too early
3333 and fail to emit constants; if it's too large we'll only look
3334 through the entire function when we could have stopped earlier. */
3335 if (cfun)
3336 n_deferred_constants++;
3337 return;
3340 output_constant_def_contents (symbol);
3343 /* Subroutine of output_constant_def_contents. Output the definition
3344 of constant EXP, which is pointed to by label LABEL. ALIGN is the
3345 constant's alignment in bits. */
3347 static void
3348 assemble_constant_contents (tree exp, const char *label, unsigned int align)
3350 HOST_WIDE_INT size;
3352 size = get_constant_size (exp);
3354 /* Do any machine/system dependent processing of the constant. */
3355 targetm.asm_out.declare_constant_name (asm_out_file, label, exp, size);
3357 /* Output the value of EXP. */
3358 output_constant (exp, size, align);
3361 /* We must output the constant data referred to by SYMBOL; do so. */
3363 static void
3364 output_constant_def_contents (rtx symbol)
3366 tree decl = SYMBOL_REF_DECL (symbol);
3367 tree exp = DECL_INITIAL (decl);
3368 unsigned int align;
3369 bool asan_protected = false;
3371 /* Make sure any other constants whose addresses appear in EXP
3372 are assigned label numbers. */
3373 output_addressed_constants (exp);
3375 /* We are no longer deferring this constant. */
3376 TREE_ASM_WRITTEN (decl) = TREE_ASM_WRITTEN (exp) = 1;
3378 if ((flag_sanitize & SANITIZE_ADDRESS)
3379 && TREE_CODE (exp) == STRING_CST
3380 && asan_protect_global (exp))
3382 asan_protected = true;
3383 DECL_ALIGN (decl) = MAX (DECL_ALIGN (decl),
3384 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
3387 /* If the constant is part of an object block, make sure that the
3388 decl has been positioned within its block, but do not write out
3389 its definition yet. output_object_blocks will do that later. */
3390 if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol))
3391 place_block_symbol (symbol);
3392 else
3394 align = DECL_ALIGN (decl);
3395 switch_to_section (get_constant_section (exp, align));
3396 if (align > BITS_PER_UNIT)
3397 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
3398 assemble_constant_contents (exp, XSTR (symbol, 0), align);
3399 if (asan_protected)
3401 HOST_WIDE_INT size = get_constant_size (exp);
3402 assemble_zeros (asan_red_zone_size (size));
3407 /* Look up EXP in the table of constant descriptors. Return the rtl
3408 if it has been emitted, else null. */
3411 lookup_constant_def (tree exp)
3413 struct constant_descriptor_tree *desc;
3414 struct constant_descriptor_tree key;
3416 key.value = exp;
3417 key.hash = const_hash_1 (exp);
3418 desc = (struct constant_descriptor_tree *)
3419 htab_find_with_hash (const_desc_htab, &key, key.hash);
3421 return (desc ? desc->rtl : NULL_RTX);
3424 /* Return a tree representing a reference to constant data in memory
3425 for the constant expression EXP.
3427 This is the counterpart of output_constant_def at the Tree level. */
3429 tree
3430 tree_output_constant_def (tree exp)
3432 struct constant_descriptor_tree *desc, key;
3433 void **loc;
3434 tree decl;
3436 /* Look up EXP in the table of constant descriptors. If we didn't find
3437 it, create a new one. */
3438 key.value = exp;
3439 key.hash = const_hash_1 (exp);
3440 loc = htab_find_slot_with_hash (const_desc_htab, &key, key.hash, INSERT);
3442 desc = (struct constant_descriptor_tree *) *loc;
3443 if (desc == 0)
3445 desc = build_constant_desc (exp);
3446 desc->hash = key.hash;
3447 *loc = desc;
3450 decl = SYMBOL_REF_DECL (XEXP (desc->rtl, 0));
3451 varpool_finalize_decl (decl);
3452 return decl;
3455 /* Used in the hash tables to avoid outputting the same constant
3456 twice. Unlike 'struct constant_descriptor_tree', RTX constants
3457 are output once per function, not once per file. */
3458 /* ??? Only a few targets need per-function constant pools. Most
3459 can use one per-file pool. Should add a targetm bit to tell the
3460 difference. */
3462 struct GTY(()) rtx_constant_pool {
3463 /* Pointers to first and last constant in pool, as ordered by offset. */
3464 struct constant_descriptor_rtx *first;
3465 struct constant_descriptor_rtx *last;
3467 /* Hash facility for making memory-constants from constant rtl-expressions.
3468 It is used on RISC machines where immediate integer arguments and
3469 constant addresses are restricted so that such constants must be stored
3470 in memory. */
3471 htab_t GTY((param_is (struct constant_descriptor_rtx))) const_rtx_htab;
3473 /* Current offset in constant pool (does not include any
3474 machine-specific header). */
3475 HOST_WIDE_INT offset;
3478 struct GTY((chain_next ("%h.next"))) constant_descriptor_rtx {
3479 struct constant_descriptor_rtx *next;
3480 rtx mem;
3481 rtx sym;
3482 rtx constant;
3483 HOST_WIDE_INT offset;
3484 hashval_t hash;
3485 enum machine_mode mode;
3486 unsigned int align;
3487 int labelno;
3488 int mark;
3491 /* Hash and compare functions for const_rtx_htab. */
3493 static hashval_t
3494 const_desc_rtx_hash (const void *ptr)
3496 const struct constant_descriptor_rtx *const desc
3497 = (const struct constant_descriptor_rtx *) ptr;
3498 return desc->hash;
3501 static int
3502 const_desc_rtx_eq (const void *a, const void *b)
3504 const struct constant_descriptor_rtx *const x
3505 = (const struct constant_descriptor_rtx *) a;
3506 const struct constant_descriptor_rtx *const y
3507 = (const struct constant_descriptor_rtx *) b;
3509 if (x->mode != y->mode)
3510 return 0;
3511 return rtx_equal_p (x->constant, y->constant);
3514 /* This is the worker function for const_rtx_hash, called via for_each_rtx. */
3516 static int
3517 const_rtx_hash_1 (rtx *xp, void *data)
3519 unsigned HOST_WIDE_INT hwi;
3520 enum machine_mode mode;
3521 enum rtx_code code;
3522 hashval_t h, *hp;
3523 rtx x;
3524 int i;
3526 x = *xp;
3527 code = GET_CODE (x);
3528 mode = GET_MODE (x);
3529 h = (hashval_t) code * 1048573 + mode;
3531 switch (code)
3533 case CONST_INT:
3534 hwi = INTVAL (x);
3536 fold_hwi:
3538 int shift = sizeof (hashval_t) * CHAR_BIT;
3539 const int n = sizeof (HOST_WIDE_INT) / sizeof (hashval_t);
3541 h ^= (hashval_t) hwi;
3542 for (i = 1; i < n; ++i)
3544 hwi >>= shift;
3545 h ^= (hashval_t) hwi;
3548 break;
3550 case CONST_WIDE_INT:
3551 hwi = GET_MODE_PRECISION (mode);
3553 for (i = 0; i < CONST_WIDE_INT_NUNITS (x); i++)
3554 hwi ^= CONST_WIDE_INT_ELT (x, i);
3555 goto fold_hwi;
3558 case CONST_DOUBLE:
3559 if (TARGET_SUPPORTS_WIDE_INT == 0 && mode == VOIDmode)
3561 hwi = CONST_DOUBLE_LOW (x) ^ CONST_DOUBLE_HIGH (x);
3562 goto fold_hwi;
3564 else
3565 h ^= real_hash (CONST_DOUBLE_REAL_VALUE (x));
3566 break;
3568 case CONST_FIXED:
3569 h ^= fixed_hash (CONST_FIXED_VALUE (x));
3570 break;
3572 case CONST_VECTOR:
3574 int i;
3575 for (i = XVECLEN (x, 0); i-- > 0; )
3576 h = h * 251 + const_rtx_hash_1 (&XVECEXP (x, 0, i), data);
3578 break;
3580 case SYMBOL_REF:
3581 h ^= htab_hash_string (XSTR (x, 0));
3582 break;
3584 case LABEL_REF:
3585 h = h * 251 + CODE_LABEL_NUMBER (XEXP (x, 0));
3586 break;
3588 case UNSPEC:
3589 case UNSPEC_VOLATILE:
3590 h = h * 251 + XINT (x, 1);
3591 break;
3593 default:
3594 break;
3597 hp = (hashval_t *) data;
3598 *hp = *hp * 509 + h;
3599 return 0;
3602 /* Compute a hash value for X, which should be a constant. */
3604 static hashval_t
3605 const_rtx_hash (rtx x)
3607 hashval_t h = 0;
3608 for_each_rtx (&x, const_rtx_hash_1, &h);
3609 return h;
3613 /* Create and return a new rtx constant pool. */
3615 static struct rtx_constant_pool *
3616 create_constant_pool (void)
3618 struct rtx_constant_pool *pool;
3620 pool = ggc_alloc<rtx_constant_pool> ();
3621 pool->const_rtx_htab = htab_create_ggc (31, const_desc_rtx_hash,
3622 const_desc_rtx_eq, NULL);
3623 pool->first = NULL;
3624 pool->last = NULL;
3625 pool->offset = 0;
3626 return pool;
3629 /* Initialize constant pool hashing for a new function. */
3631 void
3632 init_varasm_status (void)
3634 crtl->varasm.pool = create_constant_pool ();
3635 crtl->varasm.deferred_constants = 0;
3638 /* Given a MINUS expression, simplify it if both sides
3639 include the same symbol. */
3642 simplify_subtraction (rtx x)
3644 rtx r = simplify_rtx (x);
3645 return r ? r : x;
3648 /* Given a constant rtx X, make (or find) a memory constant for its value
3649 and return a MEM rtx to refer to it in memory. */
3652 force_const_mem (enum machine_mode mode, rtx x)
3654 struct constant_descriptor_rtx *desc, tmp;
3655 struct rtx_constant_pool *pool;
3656 char label[256];
3657 rtx def, symbol;
3658 hashval_t hash;
3659 unsigned int align;
3660 void **slot;
3662 /* If we're not allowed to drop X into the constant pool, don't. */
3663 if (targetm.cannot_force_const_mem (mode, x))
3664 return NULL_RTX;
3666 /* Record that this function has used a constant pool entry. */
3667 crtl->uses_const_pool = 1;
3669 /* Decide which pool to use. */
3670 pool = (targetm.use_blocks_for_constant_p (mode, x)
3671 ? shared_constant_pool
3672 : crtl->varasm.pool);
3674 /* Lookup the value in the hashtable. */
3675 tmp.constant = x;
3676 tmp.mode = mode;
3677 hash = const_rtx_hash (x);
3678 slot = htab_find_slot_with_hash (pool->const_rtx_htab, &tmp, hash, INSERT);
3679 desc = (struct constant_descriptor_rtx *) *slot;
3681 /* If the constant was already present, return its memory. */
3682 if (desc)
3683 return copy_rtx (desc->mem);
3685 /* Otherwise, create a new descriptor. */
3686 desc = ggc_alloc<constant_descriptor_rtx> ();
3687 *slot = desc;
3689 /* Align the location counter as required by EXP's data type. */
3690 align = GET_MODE_ALIGNMENT (mode == VOIDmode ? word_mode : mode);
3691 #ifdef CONSTANT_ALIGNMENT
3693 tree type = lang_hooks.types.type_for_mode (mode, 0);
3694 if (type != NULL_TREE)
3695 align = CONSTANT_ALIGNMENT (make_tree (type, x), align);
3697 #endif
3699 pool->offset += (align / BITS_PER_UNIT) - 1;
3700 pool->offset &= ~ ((align / BITS_PER_UNIT) - 1);
3702 desc->next = NULL;
3703 desc->constant = copy_rtx (tmp.constant);
3704 desc->offset = pool->offset;
3705 desc->hash = hash;
3706 desc->mode = mode;
3707 desc->align = align;
3708 desc->labelno = const_labelno;
3709 desc->mark = 0;
3711 pool->offset += GET_MODE_SIZE (mode);
3712 if (pool->last)
3713 pool->last->next = desc;
3714 else
3715 pool->first = pool->last = desc;
3716 pool->last = desc;
3718 /* Create a string containing the label name, in LABEL. */
3719 ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno);
3720 ++const_labelno;
3722 /* Construct the SYMBOL_REF. Make sure to mark it as belonging to
3723 the constants pool. */
3724 if (use_object_blocks_p () && targetm.use_blocks_for_constant_p (mode, x))
3726 section *sect = targetm.asm_out.select_rtx_section (mode, x, align);
3727 symbol = create_block_symbol (ggc_strdup (label),
3728 get_block_for_section (sect), -1);
3730 else
3731 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3732 desc->sym = symbol;
3733 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3734 CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3735 SET_SYMBOL_REF_CONSTANT (symbol, desc);
3737 /* Construct the MEM. */
3738 desc->mem = def = gen_const_mem (mode, symbol);
3739 set_mem_attributes (def, lang_hooks.types.type_for_mode (mode, 0), 1);
3740 set_mem_align (def, align);
3742 /* If we're dropping a label to the constant pool, make sure we
3743 don't delete it. */
3744 if (GET_CODE (x) == LABEL_REF)
3745 LABEL_PRESERVE_P (XEXP (x, 0)) = 1;
3747 return copy_rtx (def);
3750 /* Given a constant pool SYMBOL_REF, return the corresponding constant. */
3753 get_pool_constant (rtx addr)
3755 return SYMBOL_REF_CONSTANT (addr)->constant;
3758 /* Given a constant pool SYMBOL_REF, return the corresponding constant
3759 and whether it has been output or not. */
3762 get_pool_constant_mark (rtx addr, bool *pmarked)
3764 struct constant_descriptor_rtx *desc;
3766 desc = SYMBOL_REF_CONSTANT (addr);
3767 *pmarked = (desc->mark != 0);
3768 return desc->constant;
3771 /* Similar, return the mode. */
3773 enum machine_mode
3774 get_pool_mode (const_rtx addr)
3776 return SYMBOL_REF_CONSTANT (addr)->mode;
3779 /* Return the size of the constant pool. */
3782 get_pool_size (void)
3784 return crtl->varasm.pool->offset;
3787 /* Worker function for output_constant_pool_1. Emit assembly for X
3788 in MODE with known alignment ALIGN. */
3790 static void
3791 output_constant_pool_2 (enum machine_mode mode, rtx x, unsigned int align)
3793 switch (GET_MODE_CLASS (mode))
3795 case MODE_FLOAT:
3796 case MODE_DECIMAL_FLOAT:
3798 REAL_VALUE_TYPE r;
3800 gcc_assert (CONST_DOUBLE_AS_FLOAT_P (x));
3801 REAL_VALUE_FROM_CONST_DOUBLE (r, x);
3802 assemble_real (r, mode, align);
3803 break;
3806 case MODE_INT:
3807 case MODE_PARTIAL_INT:
3808 case MODE_FRACT:
3809 case MODE_UFRACT:
3810 case MODE_ACCUM:
3811 case MODE_UACCUM:
3812 assemble_integer (x, GET_MODE_SIZE (mode), align, 1);
3813 break;
3815 case MODE_VECTOR_FLOAT:
3816 case MODE_VECTOR_INT:
3817 case MODE_VECTOR_FRACT:
3818 case MODE_VECTOR_UFRACT:
3819 case MODE_VECTOR_ACCUM:
3820 case MODE_VECTOR_UACCUM:
3822 int i, units;
3823 enum machine_mode submode = GET_MODE_INNER (mode);
3824 unsigned int subalign = MIN (align, GET_MODE_BITSIZE (submode));
3826 gcc_assert (GET_CODE (x) == CONST_VECTOR);
3827 units = CONST_VECTOR_NUNITS (x);
3829 for (i = 0; i < units; i++)
3831 rtx elt = CONST_VECTOR_ELT (x, i);
3832 output_constant_pool_2 (submode, elt, i ? subalign : align);
3835 break;
3837 default:
3838 gcc_unreachable ();
3842 /* Worker function for output_constant_pool. Emit constant DESC,
3843 giving it ALIGN bits of alignment. */
3845 static void
3846 output_constant_pool_1 (struct constant_descriptor_rtx *desc,
3847 unsigned int align)
3849 rtx x, tmp;
3851 x = desc->constant;
3853 /* See if X is a LABEL_REF (or a CONST referring to a LABEL_REF)
3854 whose CODE_LABEL has been deleted. This can occur if a jump table
3855 is eliminated by optimization. If so, write a constant of zero
3856 instead. Note that this can also happen by turning the
3857 CODE_LABEL into a NOTE. */
3858 /* ??? This seems completely and utterly wrong. Certainly it's
3859 not true for NOTE_INSN_DELETED_LABEL, but I disbelieve proper
3860 functioning even with INSN_DELETED_P and friends. */
3862 tmp = x;
3863 switch (GET_CODE (tmp))
3865 case CONST:
3866 if (GET_CODE (XEXP (tmp, 0)) != PLUS
3867 || GET_CODE (XEXP (XEXP (tmp, 0), 0)) != LABEL_REF)
3868 break;
3869 tmp = XEXP (XEXP (tmp, 0), 0);
3870 /* FALLTHRU */
3872 case LABEL_REF:
3873 tmp = XEXP (tmp, 0);
3874 gcc_assert (!INSN_DELETED_P (tmp));
3875 gcc_assert (!NOTE_P (tmp)
3876 || NOTE_KIND (tmp) != NOTE_INSN_DELETED);
3877 break;
3879 default:
3880 break;
3883 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3884 ASM_OUTPUT_SPECIAL_POOL_ENTRY (asm_out_file, x, desc->mode,
3885 align, desc->labelno, done);
3886 #endif
3888 assemble_align (align);
3890 /* Output the label. */
3891 targetm.asm_out.internal_label (asm_out_file, "LC", desc->labelno);
3893 /* Output the data. */
3894 output_constant_pool_2 (desc->mode, x, align);
3896 /* Make sure all constants in SECTION_MERGE and not SECTION_STRINGS
3897 sections have proper size. */
3898 if (align > GET_MODE_BITSIZE (desc->mode)
3899 && in_section
3900 && (in_section->common.flags & SECTION_MERGE))
3901 assemble_align (align);
3903 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3904 done:
3905 #endif
3906 return;
3909 /* Given a SYMBOL_REF CURRENT_RTX, mark it and all constants it refers
3910 to as used. Emit referenced deferred strings. This function can
3911 be used with for_each_rtx to mark all SYMBOL_REFs in an rtx. */
3913 static int
3914 mark_constant (rtx *current_rtx, void *data ATTRIBUTE_UNUSED)
3916 rtx x = *current_rtx;
3918 if (x == NULL_RTX || GET_CODE (x) != SYMBOL_REF)
3919 return 0;
3921 if (CONSTANT_POOL_ADDRESS_P (x))
3923 struct constant_descriptor_rtx *desc = SYMBOL_REF_CONSTANT (x);
3924 if (desc->mark == 0)
3926 desc->mark = 1;
3927 for_each_rtx (&desc->constant, mark_constant, NULL);
3930 else if (TREE_CONSTANT_POOL_ADDRESS_P (x))
3932 tree decl = SYMBOL_REF_DECL (x);
3933 if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl)))
3935 n_deferred_constants--;
3936 output_constant_def_contents (x);
3940 return -1;
3943 /* Look through appropriate parts of INSN, marking all entries in the
3944 constant pool which are actually being used. Entries that are only
3945 referenced by other constants are also marked as used. Emit
3946 deferred strings that are used. */
3948 static void
3949 mark_constants (rtx insn)
3951 if (!INSN_P (insn))
3952 return;
3954 /* Insns may appear inside a SEQUENCE. Only check the patterns of
3955 insns, not any notes that may be attached. We don't want to mark
3956 a constant just because it happens to appear in a REG_EQUIV note. */
3957 if (GET_CODE (PATTERN (insn)) == SEQUENCE)
3959 rtx seq = PATTERN (insn);
3960 int i, n = XVECLEN (seq, 0);
3961 for (i = 0; i < n; ++i)
3963 rtx subinsn = XVECEXP (seq, 0, i);
3964 if (INSN_P (subinsn))
3965 for_each_rtx (&PATTERN (subinsn), mark_constant, NULL);
3968 else
3969 for_each_rtx (&PATTERN (insn), mark_constant, NULL);
3972 /* Look through the instructions for this function, and mark all the
3973 entries in POOL which are actually being used. Emit deferred constants
3974 which have indeed been used. */
3976 static void
3977 mark_constant_pool (void)
3979 rtx insn;
3981 if (!crtl->uses_const_pool && n_deferred_constants == 0)
3982 return;
3984 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
3985 mark_constants (insn);
3988 /* Write all the constants in POOL. */
3990 static void
3991 output_constant_pool_contents (struct rtx_constant_pool *pool)
3993 struct constant_descriptor_rtx *desc;
3995 for (desc = pool->first; desc ; desc = desc->next)
3996 if (desc->mark)
3998 /* If the constant is part of an object_block, make sure that
3999 the constant has been positioned within its block, but do not
4000 write out its definition yet. output_object_blocks will do
4001 that later. */
4002 if (SYMBOL_REF_HAS_BLOCK_INFO_P (desc->sym)
4003 && SYMBOL_REF_BLOCK (desc->sym))
4004 place_block_symbol (desc->sym);
4005 else
4007 switch_to_section (targetm.asm_out.select_rtx_section
4008 (desc->mode, desc->constant, desc->align));
4009 output_constant_pool_1 (desc, desc->align);
4014 /* Mark all constants that are used in the current function, then write
4015 out the function's private constant pool. */
4017 static void
4018 output_constant_pool (const char *fnname ATTRIBUTE_UNUSED,
4019 tree fndecl ATTRIBUTE_UNUSED)
4021 struct rtx_constant_pool *pool = crtl->varasm.pool;
4023 /* It is possible for gcc to call force_const_mem and then to later
4024 discard the instructions which refer to the constant. In such a
4025 case we do not need to output the constant. */
4026 mark_constant_pool ();
4028 #ifdef ASM_OUTPUT_POOL_PROLOGUE
4029 ASM_OUTPUT_POOL_PROLOGUE (asm_out_file, fnname, fndecl, pool->offset);
4030 #endif
4032 output_constant_pool_contents (pool);
4034 #ifdef ASM_OUTPUT_POOL_EPILOGUE
4035 ASM_OUTPUT_POOL_EPILOGUE (asm_out_file, fnname, fndecl, pool->offset);
4036 #endif
4039 /* Write the contents of the shared constant pool. */
4041 void
4042 output_shared_constant_pool (void)
4044 output_constant_pool_contents (shared_constant_pool);
4047 /* Determine what kind of relocations EXP may need. */
4050 compute_reloc_for_constant (tree exp)
4052 int reloc = 0, reloc2;
4053 tree tem;
4055 switch (TREE_CODE (exp))
4057 case ADDR_EXPR:
4058 case FDESC_EXPR:
4059 /* Go inside any operations that get_inner_reference can handle and see
4060 if what's inside is a constant: no need to do anything here for
4061 addresses of variables or functions. */
4062 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4063 tem = TREE_OPERAND (tem, 0))
4066 if (TREE_CODE (tem) == MEM_REF
4067 && TREE_CODE (TREE_OPERAND (tem, 0)) == ADDR_EXPR)
4069 reloc = compute_reloc_for_constant (TREE_OPERAND (tem, 0));
4070 break;
4073 if (!targetm.binds_local_p (tem))
4074 reloc |= 2;
4075 else
4076 reloc |= 1;
4077 break;
4079 case PLUS_EXPR:
4080 case POINTER_PLUS_EXPR:
4081 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4082 reloc |= compute_reloc_for_constant (TREE_OPERAND (exp, 1));
4083 break;
4085 case MINUS_EXPR:
4086 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4087 reloc2 = compute_reloc_for_constant (TREE_OPERAND (exp, 1));
4088 /* The difference of two local labels is computable at link time. */
4089 if (reloc == 1 && reloc2 == 1)
4090 reloc = 0;
4091 else
4092 reloc |= reloc2;
4093 break;
4095 CASE_CONVERT:
4096 case VIEW_CONVERT_EXPR:
4097 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4098 break;
4100 case CONSTRUCTOR:
4102 unsigned HOST_WIDE_INT idx;
4103 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4104 if (tem != 0)
4105 reloc |= compute_reloc_for_constant (tem);
4107 break;
4109 default:
4110 break;
4112 return reloc;
4115 /* Find all the constants whose addresses are referenced inside of EXP,
4116 and make sure assembler code with a label has been output for each one.
4117 Indicate whether an ADDR_EXPR has been encountered. */
4119 static void
4120 output_addressed_constants (tree exp)
4122 tree tem;
4124 switch (TREE_CODE (exp))
4126 case ADDR_EXPR:
4127 case FDESC_EXPR:
4128 /* Go inside any operations that get_inner_reference can handle and see
4129 if what's inside is a constant: no need to do anything here for
4130 addresses of variables or functions. */
4131 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4132 tem = TREE_OPERAND (tem, 0))
4135 /* If we have an initialized CONST_DECL, retrieve the initializer. */
4136 if (TREE_CODE (tem) == CONST_DECL && DECL_INITIAL (tem))
4137 tem = DECL_INITIAL (tem);
4139 if (CONSTANT_CLASS_P (tem) || TREE_CODE (tem) == CONSTRUCTOR)
4140 output_constant_def (tem, 0);
4142 if (TREE_CODE (tem) == MEM_REF)
4143 output_addressed_constants (TREE_OPERAND (tem, 0));
4144 break;
4146 case PLUS_EXPR:
4147 case POINTER_PLUS_EXPR:
4148 case MINUS_EXPR:
4149 output_addressed_constants (TREE_OPERAND (exp, 1));
4150 /* Fall through. */
4152 CASE_CONVERT:
4153 case VIEW_CONVERT_EXPR:
4154 output_addressed_constants (TREE_OPERAND (exp, 0));
4155 break;
4157 case CONSTRUCTOR:
4159 unsigned HOST_WIDE_INT idx;
4160 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4161 if (tem != 0)
4162 output_addressed_constants (tem);
4164 break;
4166 default:
4167 break;
4171 /* Whether a constructor CTOR is a valid static constant initializer if all
4172 its elements are. This used to be internal to initializer_constant_valid_p
4173 and has been exposed to let other functions like categorize_ctor_elements
4174 evaluate the property while walking a constructor for other purposes. */
4176 bool
4177 constructor_static_from_elts_p (const_tree ctor)
4179 return (TREE_CONSTANT (ctor)
4180 && (TREE_CODE (TREE_TYPE (ctor)) == UNION_TYPE
4181 || TREE_CODE (TREE_TYPE (ctor)) == RECORD_TYPE
4182 || TREE_CODE (TREE_TYPE (ctor)) == ARRAY_TYPE));
4185 static tree initializer_constant_valid_p_1 (tree value, tree endtype,
4186 tree *cache);
4188 /* A subroutine of initializer_constant_valid_p. VALUE is a MINUS_EXPR,
4189 PLUS_EXPR or POINTER_PLUS_EXPR. This looks for cases of VALUE
4190 which are valid when ENDTYPE is an integer of any size; in
4191 particular, this does not accept a pointer minus a constant. This
4192 returns null_pointer_node if the VALUE is an absolute constant
4193 which can be used to initialize a static variable. Otherwise it
4194 returns NULL. */
4196 static tree
4197 narrowing_initializer_constant_valid_p (tree value, tree endtype, tree *cache)
4199 tree op0, op1;
4201 if (!INTEGRAL_TYPE_P (endtype))
4202 return NULL_TREE;
4204 op0 = TREE_OPERAND (value, 0);
4205 op1 = TREE_OPERAND (value, 1);
4207 /* Like STRIP_NOPS except allow the operand mode to widen. This
4208 works around a feature of fold that simplifies (int)(p1 - p2) to
4209 ((int)p1 - (int)p2) under the theory that the narrower operation
4210 is cheaper. */
4212 while (CONVERT_EXPR_P (op0)
4213 || TREE_CODE (op0) == NON_LVALUE_EXPR)
4215 tree inner = TREE_OPERAND (op0, 0);
4216 if (inner == error_mark_node
4217 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4218 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op0)))
4219 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
4220 break;
4221 op0 = inner;
4224 while (CONVERT_EXPR_P (op1)
4225 || TREE_CODE (op1) == NON_LVALUE_EXPR)
4227 tree inner = TREE_OPERAND (op1, 0);
4228 if (inner == error_mark_node
4229 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4230 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op1)))
4231 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
4232 break;
4233 op1 = inner;
4236 op0 = initializer_constant_valid_p_1 (op0, endtype, cache);
4237 if (!op0)
4238 return NULL_TREE;
4240 op1 = initializer_constant_valid_p_1 (op1, endtype,
4241 cache ? cache + 2 : NULL);
4242 /* Both initializers must be known. */
4243 if (op1)
4245 if (op0 == op1
4246 && (op0 == null_pointer_node
4247 || TREE_CODE (value) == MINUS_EXPR))
4248 return null_pointer_node;
4250 /* Support differences between labels. */
4251 if (TREE_CODE (op0) == LABEL_DECL
4252 && TREE_CODE (op1) == LABEL_DECL)
4253 return null_pointer_node;
4255 if (TREE_CODE (op0) == STRING_CST
4256 && TREE_CODE (op1) == STRING_CST
4257 && operand_equal_p (op0, op1, 1))
4258 return null_pointer_node;
4261 return NULL_TREE;
4264 /* Helper function of initializer_constant_valid_p.
4265 Return nonzero if VALUE is a valid constant-valued expression
4266 for use in initializing a static variable; one that can be an
4267 element of a "constant" initializer.
4269 Return null_pointer_node if the value is absolute;
4270 if it is relocatable, return the variable that determines the relocation.
4271 We assume that VALUE has been folded as much as possible;
4272 therefore, we do not need to check for such things as
4273 arithmetic-combinations of integers.
4275 Use CACHE (pointer to 2 tree values) for caching if non-NULL. */
4277 static tree
4278 initializer_constant_valid_p_1 (tree value, tree endtype, tree *cache)
4280 tree ret;
4282 switch (TREE_CODE (value))
4284 case CONSTRUCTOR:
4285 if (constructor_static_from_elts_p (value))
4287 unsigned HOST_WIDE_INT idx;
4288 tree elt;
4289 bool absolute = true;
4291 if (cache && cache[0] == value)
4292 return cache[1];
4293 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4295 tree reloc;
4296 reloc = initializer_constant_valid_p_1 (elt, TREE_TYPE (elt),
4297 NULL);
4298 if (!reloc)
4300 if (cache)
4302 cache[0] = value;
4303 cache[1] = NULL_TREE;
4305 return NULL_TREE;
4307 if (reloc != null_pointer_node)
4308 absolute = false;
4310 /* For a non-absolute relocation, there is no single
4311 variable that can be "the variable that determines the
4312 relocation." */
4313 if (cache)
4315 cache[0] = value;
4316 cache[1] = absolute ? null_pointer_node : error_mark_node;
4318 return absolute ? null_pointer_node : error_mark_node;
4321 return TREE_STATIC (value) ? null_pointer_node : NULL_TREE;
4323 case INTEGER_CST:
4324 case VECTOR_CST:
4325 case REAL_CST:
4326 case FIXED_CST:
4327 case STRING_CST:
4328 case COMPLEX_CST:
4329 return null_pointer_node;
4331 case ADDR_EXPR:
4332 case FDESC_EXPR:
4334 tree op0 = staticp (TREE_OPERAND (value, 0));
4335 if (op0)
4337 /* "&(*a).f" is like unto pointer arithmetic. If "a" turns out
4338 to be a constant, this is old-skool offsetof-like nonsense. */
4339 if (TREE_CODE (op0) == INDIRECT_REF
4340 && TREE_CONSTANT (TREE_OPERAND (op0, 0)))
4341 return null_pointer_node;
4342 /* Taking the address of a nested function involves a trampoline,
4343 unless we don't need or want one. */
4344 if (TREE_CODE (op0) == FUNCTION_DECL
4345 && DECL_STATIC_CHAIN (op0)
4346 && !TREE_NO_TRAMPOLINE (value))
4347 return NULL_TREE;
4348 /* "&{...}" requires a temporary to hold the constructed
4349 object. */
4350 if (TREE_CODE (op0) == CONSTRUCTOR)
4351 return NULL_TREE;
4353 return op0;
4356 case NON_LVALUE_EXPR:
4357 return initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4358 endtype, cache);
4360 case VIEW_CONVERT_EXPR:
4362 tree src = TREE_OPERAND (value, 0);
4363 tree src_type = TREE_TYPE (src);
4364 tree dest_type = TREE_TYPE (value);
4366 /* Allow view-conversions from aggregate to non-aggregate type only
4367 if the bit pattern is fully preserved afterwards; otherwise, the
4368 RTL expander won't be able to apply a subsequent transformation
4369 to the underlying constructor. */
4370 if (AGGREGATE_TYPE_P (src_type) && !AGGREGATE_TYPE_P (dest_type))
4372 if (TYPE_MODE (endtype) == TYPE_MODE (dest_type))
4373 return initializer_constant_valid_p_1 (src, endtype, cache);
4374 else
4375 return NULL_TREE;
4378 /* Allow all other kinds of view-conversion. */
4379 return initializer_constant_valid_p_1 (src, endtype, cache);
4382 CASE_CONVERT:
4384 tree src = TREE_OPERAND (value, 0);
4385 tree src_type = TREE_TYPE (src);
4386 tree dest_type = TREE_TYPE (value);
4388 /* Allow conversions between pointer types, floating-point
4389 types, and offset types. */
4390 if ((POINTER_TYPE_P (dest_type) && POINTER_TYPE_P (src_type))
4391 || (FLOAT_TYPE_P (dest_type) && FLOAT_TYPE_P (src_type))
4392 || (TREE_CODE (dest_type) == OFFSET_TYPE
4393 && TREE_CODE (src_type) == OFFSET_TYPE))
4394 return initializer_constant_valid_p_1 (src, endtype, cache);
4396 /* Allow length-preserving conversions between integer types. */
4397 if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type)
4398 && (TYPE_PRECISION (dest_type) == TYPE_PRECISION (src_type)))
4399 return initializer_constant_valid_p_1 (src, endtype, cache);
4401 /* Allow conversions between other integer types only if
4402 explicit value. */
4403 if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type))
4405 tree inner = initializer_constant_valid_p_1 (src, endtype, cache);
4406 if (inner == null_pointer_node)
4407 return null_pointer_node;
4408 break;
4411 /* Allow (int) &foo provided int is as wide as a pointer. */
4412 if (INTEGRAL_TYPE_P (dest_type) && POINTER_TYPE_P (src_type)
4413 && (TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type)))
4414 return initializer_constant_valid_p_1 (src, endtype, cache);
4416 /* Likewise conversions from int to pointers, but also allow
4417 conversions from 0. */
4418 if ((POINTER_TYPE_P (dest_type)
4419 || TREE_CODE (dest_type) == OFFSET_TYPE)
4420 && INTEGRAL_TYPE_P (src_type))
4422 if (TREE_CODE (src) == INTEGER_CST
4423 && TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type))
4424 return null_pointer_node;
4425 if (integer_zerop (src))
4426 return null_pointer_node;
4427 else if (TYPE_PRECISION (dest_type) <= TYPE_PRECISION (src_type))
4428 return initializer_constant_valid_p_1 (src, endtype, cache);
4431 /* Allow conversions to struct or union types if the value
4432 inside is okay. */
4433 if (TREE_CODE (dest_type) == RECORD_TYPE
4434 || TREE_CODE (dest_type) == UNION_TYPE)
4435 return initializer_constant_valid_p_1 (src, endtype, cache);
4437 break;
4439 case POINTER_PLUS_EXPR:
4440 case PLUS_EXPR:
4441 /* Any valid floating-point constants will have been folded by now;
4442 with -frounding-math we hit this with addition of two constants. */
4443 if (TREE_CODE (endtype) == REAL_TYPE)
4444 return NULL_TREE;
4445 if (cache && cache[0] == value)
4446 return cache[1];
4447 if (! INTEGRAL_TYPE_P (endtype)
4448 || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4450 tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4451 tree valid0
4452 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4453 endtype, ncache);
4454 tree valid1
4455 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4456 endtype, ncache + 2);
4457 /* If either term is absolute, use the other term's relocation. */
4458 if (valid0 == null_pointer_node)
4459 ret = valid1;
4460 else if (valid1 == null_pointer_node)
4461 ret = valid0;
4462 /* Support narrowing pointer differences. */
4463 else
4464 ret = narrowing_initializer_constant_valid_p (value, endtype,
4465 ncache);
4467 else
4468 /* Support narrowing pointer differences. */
4469 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4470 if (cache)
4472 cache[0] = value;
4473 cache[1] = ret;
4475 return ret;
4477 case MINUS_EXPR:
4478 if (TREE_CODE (endtype) == REAL_TYPE)
4479 return NULL_TREE;
4480 if (cache && cache[0] == value)
4481 return cache[1];
4482 if (! INTEGRAL_TYPE_P (endtype)
4483 || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4485 tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4486 tree valid0
4487 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4488 endtype, ncache);
4489 tree valid1
4490 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4491 endtype, ncache + 2);
4492 /* Win if second argument is absolute. */
4493 if (valid1 == null_pointer_node)
4494 ret = valid0;
4495 /* Win if both arguments have the same relocation.
4496 Then the value is absolute. */
4497 else if (valid0 == valid1 && valid0 != 0)
4498 ret = null_pointer_node;
4499 /* Since GCC guarantees that string constants are unique in the
4500 generated code, a subtraction between two copies of the same
4501 constant string is absolute. */
4502 else if (valid0 && TREE_CODE (valid0) == STRING_CST
4503 && valid1 && TREE_CODE (valid1) == STRING_CST
4504 && operand_equal_p (valid0, valid1, 1))
4505 ret = null_pointer_node;
4506 /* Support narrowing differences. */
4507 else
4508 ret = narrowing_initializer_constant_valid_p (value, endtype,
4509 ncache);
4511 else
4512 /* Support narrowing differences. */
4513 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4514 if (cache)
4516 cache[0] = value;
4517 cache[1] = ret;
4519 return ret;
4521 default:
4522 break;
4525 return NULL_TREE;
4528 /* Return nonzero if VALUE is a valid constant-valued expression
4529 for use in initializing a static variable; one that can be an
4530 element of a "constant" initializer.
4532 Return null_pointer_node if the value is absolute;
4533 if it is relocatable, return the variable that determines the relocation.
4534 We assume that VALUE has been folded as much as possible;
4535 therefore, we do not need to check for such things as
4536 arithmetic-combinations of integers. */
4537 tree
4538 initializer_constant_valid_p (tree value, tree endtype)
4540 return initializer_constant_valid_p_1 (value, endtype, NULL);
4543 /* Return true if VALUE is a valid constant-valued expression
4544 for use in initializing a static bit-field; one that can be
4545 an element of a "constant" initializer. */
4547 bool
4548 initializer_constant_valid_for_bitfield_p (tree value)
4550 /* For bitfields we support integer constants or possibly nested aggregates
4551 of such. */
4552 switch (TREE_CODE (value))
4554 case CONSTRUCTOR:
4556 unsigned HOST_WIDE_INT idx;
4557 tree elt;
4559 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4560 if (!initializer_constant_valid_for_bitfield_p (elt))
4561 return false;
4562 return true;
4565 case INTEGER_CST:
4566 case REAL_CST:
4567 return true;
4569 case VIEW_CONVERT_EXPR:
4570 case NON_LVALUE_EXPR:
4571 return
4572 initializer_constant_valid_for_bitfield_p (TREE_OPERAND (value, 0));
4574 default:
4575 break;
4578 return false;
4581 /* output_constructor outer state of relevance in recursive calls, typically
4582 for nested aggregate bitfields. */
4584 typedef struct {
4585 unsigned int bit_offset; /* current position in ... */
4586 int byte; /* ... the outer byte buffer. */
4587 } oc_outer_state;
4589 static unsigned HOST_WIDE_INT
4590 output_constructor (tree, unsigned HOST_WIDE_INT, unsigned int,
4591 oc_outer_state *);
4593 /* Output assembler code for constant EXP, with no label.
4594 This includes the pseudo-op such as ".int" or ".byte", and a newline.
4595 Assumes output_addressed_constants has been done on EXP already.
4597 Generate at least SIZE bytes of assembler data, padding at the end
4598 with zeros if necessary. SIZE must always be specified. The returned
4599 value is the actual number of bytes of assembler data generated, which
4600 may be bigger than SIZE if the object contains a variable length field.
4602 SIZE is important for structure constructors,
4603 since trailing members may have been omitted from the constructor.
4604 It is also important for initialization of arrays from string constants
4605 since the full length of the string constant might not be wanted.
4606 It is also needed for initialization of unions, where the initializer's
4607 type is just one member, and that may not be as long as the union.
4609 There a case in which we would fail to output exactly SIZE bytes:
4610 for a structure constructor that wants to produce more than SIZE bytes.
4611 But such constructors will never be generated for any possible input.
4613 ALIGN is the alignment of the data in bits. */
4615 static unsigned HOST_WIDE_INT
4616 output_constant (tree exp, unsigned HOST_WIDE_INT size, unsigned int align)
4618 enum tree_code code;
4619 unsigned HOST_WIDE_INT thissize;
4621 if (size == 0 || flag_syntax_only)
4622 return size;
4624 /* See if we're trying to initialize a pointer in a non-default mode
4625 to the address of some declaration somewhere. If the target says
4626 the mode is valid for pointers, assume the target has a way of
4627 resolving it. */
4628 if (TREE_CODE (exp) == NOP_EXPR
4629 && POINTER_TYPE_P (TREE_TYPE (exp))
4630 && targetm.addr_space.valid_pointer_mode
4631 (TYPE_MODE (TREE_TYPE (exp)),
4632 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4634 tree saved_type = TREE_TYPE (exp);
4636 /* Peel off any intermediate conversions-to-pointer for valid
4637 pointer modes. */
4638 while (TREE_CODE (exp) == NOP_EXPR
4639 && POINTER_TYPE_P (TREE_TYPE (exp))
4640 && targetm.addr_space.valid_pointer_mode
4641 (TYPE_MODE (TREE_TYPE (exp)),
4642 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4643 exp = TREE_OPERAND (exp, 0);
4645 /* If what we're left with is the address of something, we can
4646 convert the address to the final type and output it that
4647 way. */
4648 if (TREE_CODE (exp) == ADDR_EXPR)
4649 exp = build1 (ADDR_EXPR, saved_type, TREE_OPERAND (exp, 0));
4650 /* Likewise for constant ints. */
4651 else if (TREE_CODE (exp) == INTEGER_CST)
4652 exp = wide_int_to_tree (saved_type, exp);
4656 /* Eliminate any conversions since we'll be outputting the underlying
4657 constant. */
4658 while (CONVERT_EXPR_P (exp)
4659 || TREE_CODE (exp) == NON_LVALUE_EXPR
4660 || TREE_CODE (exp) == VIEW_CONVERT_EXPR)
4662 HOST_WIDE_INT type_size = int_size_in_bytes (TREE_TYPE (exp));
4663 HOST_WIDE_INT op_size = int_size_in_bytes (TREE_TYPE (TREE_OPERAND (exp, 0)));
4665 /* Make sure eliminating the conversion is really a no-op, except with
4666 VIEW_CONVERT_EXPRs to allow for wild Ada unchecked conversions and
4667 union types to allow for Ada unchecked unions. */
4668 if (type_size > op_size
4669 && TREE_CODE (exp) != VIEW_CONVERT_EXPR
4670 && TREE_CODE (TREE_TYPE (exp)) != UNION_TYPE)
4671 /* Keep the conversion. */
4672 break;
4673 else
4674 exp = TREE_OPERAND (exp, 0);
4677 code = TREE_CODE (TREE_TYPE (exp));
4678 thissize = int_size_in_bytes (TREE_TYPE (exp));
4680 /* Allow a constructor with no elements for any data type.
4681 This means to fill the space with zeros. */
4682 if (TREE_CODE (exp) == CONSTRUCTOR
4683 && vec_safe_is_empty (CONSTRUCTOR_ELTS (exp)))
4685 assemble_zeros (size);
4686 return size;
4689 if (TREE_CODE (exp) == FDESC_EXPR)
4691 #ifdef ASM_OUTPUT_FDESC
4692 HOST_WIDE_INT part = tree_to_shwi (TREE_OPERAND (exp, 1));
4693 tree decl = TREE_OPERAND (exp, 0);
4694 ASM_OUTPUT_FDESC (asm_out_file, decl, part);
4695 #else
4696 gcc_unreachable ();
4697 #endif
4698 return size;
4701 /* Now output the underlying data. If we've handling the padding, return.
4702 Otherwise, break and ensure SIZE is the size written. */
4703 switch (code)
4705 case BOOLEAN_TYPE:
4706 case INTEGER_TYPE:
4707 case ENUMERAL_TYPE:
4708 case POINTER_TYPE:
4709 case REFERENCE_TYPE:
4710 case OFFSET_TYPE:
4711 case FIXED_POINT_TYPE:
4712 case NULLPTR_TYPE:
4713 if (! assemble_integer (expand_expr (exp, NULL_RTX, VOIDmode,
4714 EXPAND_INITIALIZER),
4715 MIN (size, thissize), align, 0))
4716 error ("initializer for integer/fixed-point value is too complicated");
4717 break;
4719 case REAL_TYPE:
4720 if (TREE_CODE (exp) != REAL_CST)
4721 error ("initializer for floating value is not a floating constant");
4722 else
4723 assemble_real (TREE_REAL_CST (exp), TYPE_MODE (TREE_TYPE (exp)), align);
4724 break;
4726 case COMPLEX_TYPE:
4727 output_constant (TREE_REALPART (exp), thissize / 2, align);
4728 output_constant (TREE_IMAGPART (exp), thissize / 2,
4729 min_align (align, BITS_PER_UNIT * (thissize / 2)));
4730 break;
4732 case ARRAY_TYPE:
4733 case VECTOR_TYPE:
4734 switch (TREE_CODE (exp))
4736 case CONSTRUCTOR:
4737 return output_constructor (exp, size, align, NULL);
4738 case STRING_CST:
4739 thissize
4740 = MIN ((unsigned HOST_WIDE_INT)TREE_STRING_LENGTH (exp), size);
4741 assemble_string (TREE_STRING_POINTER (exp), thissize);
4742 break;
4743 case VECTOR_CST:
4745 enum machine_mode inner = TYPE_MODE (TREE_TYPE (TREE_TYPE (exp)));
4746 unsigned int nalign = MIN (align, GET_MODE_ALIGNMENT (inner));
4747 int elt_size = GET_MODE_SIZE (inner);
4748 output_constant (VECTOR_CST_ELT (exp, 0), elt_size, align);
4749 thissize = elt_size;
4750 for (unsigned int i = 1; i < VECTOR_CST_NELTS (exp); i++)
4752 output_constant (VECTOR_CST_ELT (exp, i), elt_size, nalign);
4753 thissize += elt_size;
4755 break;
4757 default:
4758 gcc_unreachable ();
4760 break;
4762 case RECORD_TYPE:
4763 case UNION_TYPE:
4764 gcc_assert (TREE_CODE (exp) == CONSTRUCTOR);
4765 return output_constructor (exp, size, align, NULL);
4767 case ERROR_MARK:
4768 return 0;
4770 default:
4771 gcc_unreachable ();
4774 if (size > thissize)
4775 assemble_zeros (size - thissize);
4777 return size;
4781 /* Subroutine of output_constructor, used for computing the size of
4782 arrays of unspecified length. VAL must be a CONSTRUCTOR of an array
4783 type with an unspecified upper bound. */
4785 static unsigned HOST_WIDE_INT
4786 array_size_for_constructor (tree val)
4788 tree max_index;
4789 unsigned HOST_WIDE_INT cnt;
4790 tree index, value, tmp;
4791 offset_int i;
4793 /* This code used to attempt to handle string constants that are not
4794 arrays of single-bytes, but nothing else does, so there's no point in
4795 doing it here. */
4796 if (TREE_CODE (val) == STRING_CST)
4797 return TREE_STRING_LENGTH (val);
4799 max_index = NULL_TREE;
4800 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (val), cnt, index, value)
4802 if (TREE_CODE (index) == RANGE_EXPR)
4803 index = TREE_OPERAND (index, 1);
4804 if (max_index == NULL_TREE || tree_int_cst_lt (max_index, index))
4805 max_index = index;
4808 if (max_index == NULL_TREE)
4809 return 0;
4811 /* Compute the total number of array elements. */
4812 tmp = TYPE_MIN_VALUE (TYPE_DOMAIN (TREE_TYPE (val)));
4813 i = wi::to_offset (max_index) - wi::to_offset (tmp) + 1;
4815 /* Multiply by the array element unit size to find number of bytes. */
4816 i *= wi::to_offset (TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (val))));
4818 gcc_assert (wi::fits_uhwi_p (i));
4819 return i.to_uhwi ();
4822 /* Other datastructures + helpers for output_constructor. */
4824 /* output_constructor local state to support interaction with helpers. */
4826 typedef struct {
4828 /* Received arguments. */
4829 tree exp; /* Constructor expression. */
4830 tree type; /* Type of constructor expression. */
4831 unsigned HOST_WIDE_INT size; /* # bytes to output - pad if necessary. */
4832 unsigned int align; /* Known initial alignment. */
4833 tree min_index; /* Lower bound if specified for an array. */
4835 /* Output processing state. */
4836 HOST_WIDE_INT total_bytes; /* # bytes output so far / current position. */
4837 int byte; /* Part of a bitfield byte yet to be output. */
4838 int last_relative_index; /* Implicit or explicit index of the last
4839 array element output within a bitfield. */
4840 bool byte_buffer_in_use; /* Whether BYTE is in use. */
4842 /* Current element. */
4843 tree field; /* Current field decl in a record. */
4844 tree val; /* Current element value. */
4845 tree index; /* Current element index. */
4847 } oc_local_state;
4849 /* Helper for output_constructor. From the current LOCAL state, output a
4850 RANGE_EXPR element. */
4852 static void
4853 output_constructor_array_range (oc_local_state *local)
4855 unsigned HOST_WIDE_INT fieldsize
4856 = int_size_in_bytes (TREE_TYPE (local->type));
4858 HOST_WIDE_INT lo_index
4859 = tree_to_shwi (TREE_OPERAND (local->index, 0));
4860 HOST_WIDE_INT hi_index
4861 = tree_to_shwi (TREE_OPERAND (local->index, 1));
4862 HOST_WIDE_INT index;
4864 unsigned int align2
4865 = min_align (local->align, fieldsize * BITS_PER_UNIT);
4867 for (index = lo_index; index <= hi_index; index++)
4869 /* Output the element's initial value. */
4870 if (local->val == NULL_TREE)
4871 assemble_zeros (fieldsize);
4872 else
4873 fieldsize = output_constant (local->val, fieldsize, align2);
4875 /* Count its size. */
4876 local->total_bytes += fieldsize;
4880 /* Helper for output_constructor. From the current LOCAL state, output a
4881 field element that is not true bitfield or part of an outer one. */
4883 static void
4884 output_constructor_regular_field (oc_local_state *local)
4886 /* Field size and position. Since this structure is static, we know the
4887 positions are constant. */
4888 unsigned HOST_WIDE_INT fieldsize;
4889 HOST_WIDE_INT fieldpos;
4891 unsigned int align2;
4893 if (local->index != NULL_TREE)
4895 /* Perform the index calculation in modulo arithmetic but
4896 sign-extend the result because Ada has negative DECL_FIELD_OFFSETs
4897 but we are using an unsigned sizetype. */
4898 unsigned prec = TYPE_PRECISION (sizetype);
4899 offset_int idx = wi::sext (wi::to_offset (local->index)
4900 - wi::to_offset (local->min_index), prec);
4901 fieldpos = (idx * wi::to_offset (TYPE_SIZE_UNIT (TREE_TYPE (local->val))))
4902 .to_short_addr ();
4904 else if (local->field != NULL_TREE)
4905 fieldpos = int_byte_position (local->field);
4906 else
4907 fieldpos = 0;
4909 /* Output any buffered-up bit-fields preceding this element. */
4910 if (local->byte_buffer_in_use)
4912 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
4913 local->total_bytes++;
4914 local->byte_buffer_in_use = false;
4917 /* Advance to offset of this element.
4918 Note no alignment needed in an array, since that is guaranteed
4919 if each element has the proper size. */
4920 if ((local->field != NULL_TREE || local->index != NULL_TREE)
4921 && fieldpos > local->total_bytes)
4923 assemble_zeros (fieldpos - local->total_bytes);
4924 local->total_bytes = fieldpos;
4927 /* Find the alignment of this element. */
4928 align2 = min_align (local->align, BITS_PER_UNIT * fieldpos);
4930 /* Determine size this element should occupy. */
4931 if (local->field)
4933 fieldsize = 0;
4935 /* If this is an array with an unspecified upper bound,
4936 the initializer determines the size. */
4937 /* ??? This ought to only checked if DECL_SIZE_UNIT is NULL,
4938 but we cannot do this until the deprecated support for
4939 initializing zero-length array members is removed. */
4940 if (TREE_CODE (TREE_TYPE (local->field)) == ARRAY_TYPE
4941 && TYPE_DOMAIN (TREE_TYPE (local->field))
4942 && ! TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (local->field))))
4944 fieldsize = array_size_for_constructor (local->val);
4945 /* Given a non-empty initialization, this field had
4946 better be last. */
4947 gcc_assert (!fieldsize || !DECL_CHAIN (local->field));
4949 else
4950 fieldsize = tree_to_uhwi (DECL_SIZE_UNIT (local->field));
4952 else
4953 fieldsize = int_size_in_bytes (TREE_TYPE (local->type));
4955 /* Output the element's initial value. */
4956 if (local->val == NULL_TREE)
4957 assemble_zeros (fieldsize);
4958 else
4959 fieldsize = output_constant (local->val, fieldsize, align2);
4961 /* Count its size. */
4962 local->total_bytes += fieldsize;
4965 /* Helper for output_constructor. From the LOCAL state, output an element
4966 that is a true bitfield or part of an outer one. BIT_OFFSET is the offset
4967 from the start of a possibly ongoing outer byte buffer. */
4969 static void
4970 output_constructor_bitfield (oc_local_state *local, unsigned int bit_offset)
4972 /* Bit size of this element. */
4973 HOST_WIDE_INT ebitsize
4974 = (local->field
4975 ? tree_to_uhwi (DECL_SIZE (local->field))
4976 : tree_to_uhwi (TYPE_SIZE (TREE_TYPE (local->type))));
4978 /* Relative index of this element if this is an array component. */
4979 HOST_WIDE_INT relative_index
4980 = (!local->field
4981 ? (local->index
4982 ? (tree_to_shwi (local->index)
4983 - tree_to_shwi (local->min_index))
4984 : local->last_relative_index + 1)
4985 : 0);
4987 /* Bit position of this element from the start of the containing
4988 constructor. */
4989 HOST_WIDE_INT constructor_relative_ebitpos
4990 = (local->field
4991 ? int_bit_position (local->field)
4992 : ebitsize * relative_index);
4994 /* Bit position of this element from the start of a possibly ongoing
4995 outer byte buffer. */
4996 HOST_WIDE_INT byte_relative_ebitpos
4997 = bit_offset + constructor_relative_ebitpos;
4999 /* From the start of a possibly ongoing outer byte buffer, offsets to
5000 the first bit of this element and to the first bit past the end of
5001 this element. */
5002 HOST_WIDE_INT next_offset = byte_relative_ebitpos;
5003 HOST_WIDE_INT end_offset = byte_relative_ebitpos + ebitsize;
5005 local->last_relative_index = relative_index;
5007 if (local->val == NULL_TREE)
5008 local->val = integer_zero_node;
5010 while (TREE_CODE (local->val) == VIEW_CONVERT_EXPR
5011 || TREE_CODE (local->val) == NON_LVALUE_EXPR)
5012 local->val = TREE_OPERAND (local->val, 0);
5014 if (TREE_CODE (local->val) != INTEGER_CST
5015 && TREE_CODE (local->val) != CONSTRUCTOR)
5017 error ("invalid initial value for member %qE", DECL_NAME (local->field));
5018 return;
5021 /* If this field does not start in this (or next) byte, skip some bytes. */
5022 if (next_offset / BITS_PER_UNIT != local->total_bytes)
5024 /* Output remnant of any bit field in previous bytes. */
5025 if (local->byte_buffer_in_use)
5027 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5028 local->total_bytes++;
5029 local->byte_buffer_in_use = false;
5032 /* If still not at proper byte, advance to there. */
5033 if (next_offset / BITS_PER_UNIT != local->total_bytes)
5035 gcc_assert (next_offset / BITS_PER_UNIT >= local->total_bytes);
5036 assemble_zeros (next_offset / BITS_PER_UNIT - local->total_bytes);
5037 local->total_bytes = next_offset / BITS_PER_UNIT;
5041 /* Set up the buffer if necessary. */
5042 if (!local->byte_buffer_in_use)
5044 local->byte = 0;
5045 if (ebitsize > 0)
5046 local->byte_buffer_in_use = true;
5049 /* If this is nested constructor, recurse passing the bit offset and the
5050 pending data, then retrieve the new pending data afterwards. */
5051 if (TREE_CODE (local->val) == CONSTRUCTOR)
5053 oc_outer_state temp_state;
5054 temp_state.bit_offset = next_offset % BITS_PER_UNIT;
5055 temp_state.byte = local->byte;
5056 local->total_bytes
5057 += output_constructor (local->val, 0, 0, &temp_state);
5058 local->byte = temp_state.byte;
5059 return;
5062 /* Otherwise, we must split the element into pieces that fall within
5063 separate bytes, and combine each byte with previous or following
5064 bit-fields. */
5065 while (next_offset < end_offset)
5067 int this_time;
5068 int shift;
5069 HOST_WIDE_INT value;
5070 HOST_WIDE_INT next_byte = next_offset / BITS_PER_UNIT;
5071 HOST_WIDE_INT next_bit = next_offset % BITS_PER_UNIT;
5073 /* Advance from byte to byte within this element when necessary. */
5074 while (next_byte != local->total_bytes)
5076 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5077 local->total_bytes++;
5078 local->byte = 0;
5081 /* Number of bits we can process at once (all part of the same byte). */
5082 this_time = MIN (end_offset - next_offset, BITS_PER_UNIT - next_bit);
5083 if (BYTES_BIG_ENDIAN)
5085 /* On big-endian machine, take the most significant bits (of the
5086 bits that are significant) first and put them into bytes from
5087 the most significant end. */
5088 shift = end_offset - next_offset - this_time;
5090 /* Don't try to take a bunch of bits that cross
5091 the word boundary in the INTEGER_CST. We can
5092 only select bits from one element. */
5093 if ((shift / HOST_BITS_PER_WIDE_INT)
5094 != ((shift + this_time - 1) / HOST_BITS_PER_WIDE_INT))
5096 const int end = shift + this_time - 1;
5097 shift = end & -HOST_BITS_PER_WIDE_INT;
5098 this_time = end - shift + 1;
5101 /* Now get the bits from the appropriate constant word. */
5102 value = TREE_INT_CST_ELT (local->val, shift / HOST_BITS_PER_WIDE_INT);
5103 shift = shift & (HOST_BITS_PER_WIDE_INT - 1);
5105 /* Get the result. This works only when:
5106 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
5107 local->byte |= (((value >> shift)
5108 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
5109 << (BITS_PER_UNIT - this_time - next_bit));
5111 else
5113 /* On little-endian machines, take the least significant bits of
5114 the value first and pack them starting at the least significant
5115 bits of the bytes. */
5116 shift = next_offset - byte_relative_ebitpos;
5118 /* Don't try to take a bunch of bits that cross
5119 the word boundary in the INTEGER_CST. We can
5120 only select bits from one element. */
5121 if ((shift / HOST_BITS_PER_WIDE_INT)
5122 != ((shift + this_time - 1) / HOST_BITS_PER_WIDE_INT))
5123 this_time
5124 = HOST_BITS_PER_WIDE_INT - (shift & (HOST_BITS_PER_WIDE_INT - 1));
5126 /* Now get the bits from the appropriate constant word. */
5127 value = TREE_INT_CST_ELT (local->val, shift / HOST_BITS_PER_WIDE_INT);
5128 shift = shift & (HOST_BITS_PER_WIDE_INT - 1);
5130 /* Get the result. This works only when:
5131 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
5132 local->byte |= (((value >> shift)
5133 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
5134 << next_bit);
5137 next_offset += this_time;
5138 local->byte_buffer_in_use = true;
5142 /* Subroutine of output_constant, used for CONSTRUCTORs (aggregate constants).
5143 Generate at least SIZE bytes, padding if necessary. OUTER designates the
5144 caller output state of relevance in recursive invocations. */
5146 static unsigned HOST_WIDE_INT
5147 output_constructor (tree exp, unsigned HOST_WIDE_INT size,
5148 unsigned int align, oc_outer_state *outer)
5150 unsigned HOST_WIDE_INT cnt;
5151 constructor_elt *ce;
5153 oc_local_state local;
5155 /* Setup our local state to communicate with helpers. */
5156 local.exp = exp;
5157 local.type = TREE_TYPE (exp);
5158 local.size = size;
5159 local.align = align;
5160 if (TREE_CODE (local.type) == ARRAY_TYPE && TYPE_DOMAIN (local.type))
5161 local.min_index = TYPE_MIN_VALUE (TYPE_DOMAIN (local.type));
5162 else
5163 local.min_index = NULL_TREE;
5165 local.total_bytes = 0;
5166 local.byte_buffer_in_use = outer != NULL;
5167 local.byte = outer ? outer->byte : 0;
5168 local.last_relative_index = -1;
5170 gcc_assert (HOST_BITS_PER_WIDE_INT >= BITS_PER_UNIT);
5172 /* As CE goes through the elements of the constant, FIELD goes through the
5173 structure fields if the constant is a structure. If the constant is a
5174 union, we override this by getting the field from the TREE_LIST element.
5175 But the constant could also be an array. Then FIELD is zero.
5177 There is always a maximum of one element in the chain LINK for unions
5178 (even if the initializer in a source program incorrectly contains
5179 more one). */
5181 if (TREE_CODE (local.type) == RECORD_TYPE)
5182 local.field = TYPE_FIELDS (local.type);
5183 else
5184 local.field = NULL_TREE;
5186 for (cnt = 0;
5187 vec_safe_iterate (CONSTRUCTOR_ELTS (exp), cnt, &ce);
5188 cnt++, local.field = local.field ? DECL_CHAIN (local.field) : 0)
5190 local.val = ce->value;
5191 local.index = NULL_TREE;
5193 /* The element in a union constructor specifies the proper field
5194 or index. */
5195 if (RECORD_OR_UNION_TYPE_P (local.type) && ce->index != NULL_TREE)
5196 local.field = ce->index;
5198 else if (TREE_CODE (local.type) == ARRAY_TYPE)
5199 local.index = ce->index;
5201 if (local.field && flag_verbose_asm)
5202 fprintf (asm_out_file, "%s %s:\n",
5203 ASM_COMMENT_START,
5204 DECL_NAME (local.field)
5205 ? IDENTIFIER_POINTER (DECL_NAME (local.field))
5206 : "<anonymous>");
5208 /* Eliminate the marker that makes a cast not be an lvalue. */
5209 if (local.val != NULL_TREE)
5210 STRIP_NOPS (local.val);
5212 /* Output the current element, using the appropriate helper ... */
5214 /* For an array slice not part of an outer bitfield. */
5215 if (!outer
5216 && local.index != NULL_TREE
5217 && TREE_CODE (local.index) == RANGE_EXPR)
5218 output_constructor_array_range (&local);
5220 /* For a field that is neither a true bitfield nor part of an outer one,
5221 known to be at least byte aligned and multiple-of-bytes long. */
5222 else if (!outer
5223 && (local.field == NULL_TREE
5224 || !CONSTRUCTOR_BITFIELD_P (local.field)))
5225 output_constructor_regular_field (&local);
5227 /* For a true bitfield or part of an outer one. Only INTEGER_CSTs are
5228 supported for scalar fields, so we may need to convert first. */
5229 else
5231 if (TREE_CODE (local.val) == REAL_CST)
5232 local.val
5233 = fold_unary (VIEW_CONVERT_EXPR,
5234 build_nonstandard_integer_type
5235 (TYPE_PRECISION (TREE_TYPE (local.val)), 0),
5236 local.val);
5237 output_constructor_bitfield (&local, outer ? outer->bit_offset : 0);
5241 /* If we are not at toplevel, save the pending data for our caller.
5242 Otherwise output the pending data and padding zeros as needed. */
5243 if (outer)
5244 outer->byte = local.byte;
5245 else
5247 if (local.byte_buffer_in_use)
5249 assemble_integer (GEN_INT (local.byte), 1, BITS_PER_UNIT, 1);
5250 local.total_bytes++;
5253 if ((unsigned HOST_WIDE_INT)local.total_bytes < local.size)
5255 assemble_zeros (local.size - local.total_bytes);
5256 local.total_bytes = local.size;
5260 return local.total_bytes;
5263 /* Mark DECL as weak. */
5265 static void
5266 mark_weak (tree decl)
5268 DECL_WEAK (decl) = 1;
5270 if (DECL_RTL_SET_P (decl)
5271 && MEM_P (DECL_RTL (decl))
5272 && XEXP (DECL_RTL (decl), 0)
5273 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == SYMBOL_REF)
5274 SYMBOL_REF_WEAK (XEXP (DECL_RTL (decl), 0)) = 1;
5277 /* Merge weak status between NEWDECL and OLDDECL. */
5279 void
5280 merge_weak (tree newdecl, tree olddecl)
5282 if (DECL_WEAK (newdecl) == DECL_WEAK (olddecl))
5284 if (DECL_WEAK (newdecl) && TARGET_SUPPORTS_WEAK)
5286 tree *pwd;
5287 /* We put the NEWDECL on the weak_decls list at some point
5288 and OLDDECL as well. Keep just OLDDECL on the list. */
5289 for (pwd = &weak_decls; *pwd; pwd = &TREE_CHAIN (*pwd))
5290 if (TREE_VALUE (*pwd) == newdecl)
5292 *pwd = TREE_CHAIN (*pwd);
5293 break;
5296 return;
5299 if (DECL_WEAK (newdecl))
5301 tree wd;
5303 /* NEWDECL is weak, but OLDDECL is not. */
5305 /* If we already output the OLDDECL, we're in trouble; we can't
5306 go back and make it weak. This should never happen in
5307 unit-at-a-time compilation. */
5308 gcc_assert (!TREE_ASM_WRITTEN (olddecl));
5310 /* If we've already generated rtl referencing OLDDECL, we may
5311 have done so in a way that will not function properly with
5312 a weak symbol. Again in unit-at-a-time this should be
5313 impossible. */
5314 gcc_assert (!TREE_USED (olddecl)
5315 || !TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (olddecl)));
5317 if (TARGET_SUPPORTS_WEAK)
5319 /* We put the NEWDECL on the weak_decls list at some point.
5320 Replace it with the OLDDECL. */
5321 for (wd = weak_decls; wd; wd = TREE_CHAIN (wd))
5322 if (TREE_VALUE (wd) == newdecl)
5324 TREE_VALUE (wd) = olddecl;
5325 break;
5327 /* We may not find the entry on the list. If NEWDECL is a
5328 weak alias, then we will have already called
5329 globalize_decl to remove the entry; in that case, we do
5330 not need to do anything. */
5333 /* Make the OLDDECL weak; it's OLDDECL that we'll be keeping. */
5334 mark_weak (olddecl);
5336 else
5337 /* OLDDECL was weak, but NEWDECL was not explicitly marked as
5338 weak. Just update NEWDECL to indicate that it's weak too. */
5339 mark_weak (newdecl);
5342 /* Declare DECL to be a weak symbol. */
5344 void
5345 declare_weak (tree decl)
5347 gcc_assert (TREE_CODE (decl) != FUNCTION_DECL || !TREE_ASM_WRITTEN (decl));
5348 if (! TREE_PUBLIC (decl))
5349 error ("weak declaration of %q+D must be public", decl);
5350 else if (!TARGET_SUPPORTS_WEAK)
5351 warning (0, "weak declaration of %q+D not supported", decl);
5353 mark_weak (decl);
5354 if (!lookup_attribute ("weak", DECL_ATTRIBUTES (decl)))
5355 DECL_ATTRIBUTES (decl)
5356 = tree_cons (get_identifier ("weak"), NULL, DECL_ATTRIBUTES (decl));
5359 static void
5360 weak_finish_1 (tree decl)
5362 #if defined (ASM_WEAKEN_DECL) || defined (ASM_WEAKEN_LABEL)
5363 const char *const name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5364 #endif
5366 if (! TREE_USED (decl))
5367 return;
5369 #ifdef ASM_WEAKEN_DECL
5370 ASM_WEAKEN_DECL (asm_out_file, decl, name, NULL);
5371 #else
5372 #ifdef ASM_WEAKEN_LABEL
5373 ASM_WEAKEN_LABEL (asm_out_file, name);
5374 #else
5375 #ifdef ASM_OUTPUT_WEAK_ALIAS
5377 static bool warn_once = 0;
5378 if (! warn_once)
5380 warning (0, "only weak aliases are supported in this configuration");
5381 warn_once = 1;
5383 return;
5385 #endif
5386 #endif
5387 #endif
5390 /* Fiven an assembly name, find the decl it is associated with. */
5391 static tree
5392 find_decl (tree target)
5394 symtab_node *node = symtab_node_for_asm (target);
5395 if (node)
5396 return node->decl;
5397 return NULL_TREE;
5400 /* This TREE_LIST contains weakref targets. */
5402 static GTY(()) tree weakref_targets;
5404 /* Emit any pending weak declarations. */
5406 void
5407 weak_finish (void)
5409 tree t;
5411 for (t = weakref_targets; t; t = TREE_CHAIN (t))
5413 tree alias_decl = TREE_PURPOSE (t);
5414 tree target = ultimate_transparent_alias_target (&TREE_VALUE (t));
5416 if (! TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (alias_decl)))
5417 /* Remove alias_decl from the weak list, but leave entries for
5418 the target alone. */
5419 target = NULL_TREE;
5420 #ifndef ASM_OUTPUT_WEAKREF
5421 else if (! TREE_SYMBOL_REFERENCED (target))
5423 /* Use ASM_WEAKEN_LABEL only if ASM_WEAKEN_DECL is not
5424 defined, otherwise we and weak_finish_1 would use
5425 different macros. */
5426 # if defined ASM_WEAKEN_LABEL && ! defined ASM_WEAKEN_DECL
5427 ASM_WEAKEN_LABEL (asm_out_file, IDENTIFIER_POINTER (target));
5428 # else
5429 tree decl = find_decl (target);
5431 if (! decl)
5433 decl = build_decl (DECL_SOURCE_LOCATION (alias_decl),
5434 TREE_CODE (alias_decl), target,
5435 TREE_TYPE (alias_decl));
5437 DECL_EXTERNAL (decl) = 1;
5438 TREE_PUBLIC (decl) = 1;
5439 DECL_ARTIFICIAL (decl) = 1;
5440 TREE_NOTHROW (decl) = TREE_NOTHROW (alias_decl);
5441 TREE_USED (decl) = 1;
5444 weak_finish_1 (decl);
5445 # endif
5447 #endif
5450 tree *p;
5451 tree t2;
5453 /* Remove the alias and the target from the pending weak list
5454 so that we do not emit any .weak directives for the former,
5455 nor multiple .weak directives for the latter. */
5456 for (p = &weak_decls; (t2 = *p) ; )
5458 if (TREE_VALUE (t2) == alias_decl
5459 || target == DECL_ASSEMBLER_NAME (TREE_VALUE (t2)))
5460 *p = TREE_CHAIN (t2);
5461 else
5462 p = &TREE_CHAIN (t2);
5465 /* Remove other weakrefs to the same target, to speed things up. */
5466 for (p = &TREE_CHAIN (t); (t2 = *p) ; )
5468 if (target == ultimate_transparent_alias_target (&TREE_VALUE (t2)))
5469 *p = TREE_CHAIN (t2);
5470 else
5471 p = &TREE_CHAIN (t2);
5476 for (t = weak_decls; t; t = TREE_CHAIN (t))
5478 tree decl = TREE_VALUE (t);
5480 weak_finish_1 (decl);
5484 /* Emit the assembly bits to indicate that DECL is globally visible. */
5486 static void
5487 globalize_decl (tree decl)
5490 #if defined (ASM_WEAKEN_LABEL) || defined (ASM_WEAKEN_DECL)
5491 if (DECL_WEAK (decl))
5493 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
5494 tree *p, t;
5496 #ifdef ASM_WEAKEN_DECL
5497 ASM_WEAKEN_DECL (asm_out_file, decl, name, 0);
5498 #else
5499 ASM_WEAKEN_LABEL (asm_out_file, name);
5500 #endif
5502 /* Remove this function from the pending weak list so that
5503 we do not emit multiple .weak directives for it. */
5504 for (p = &weak_decls; (t = *p) ; )
5506 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5507 *p = TREE_CHAIN (t);
5508 else
5509 p = &TREE_CHAIN (t);
5512 /* Remove weakrefs to the same target from the pending weakref
5513 list, for the same reason. */
5514 for (p = &weakref_targets; (t = *p) ; )
5516 if (DECL_ASSEMBLER_NAME (decl)
5517 == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5518 *p = TREE_CHAIN (t);
5519 else
5520 p = &TREE_CHAIN (t);
5523 return;
5525 #endif
5527 targetm.asm_out.globalize_decl_name (asm_out_file, decl);
5530 vec<alias_pair, va_gc> *alias_pairs;
5532 /* Output the assembler code for a define (equate) using ASM_OUTPUT_DEF
5533 or ASM_OUTPUT_DEF_FROM_DECLS. The function defines the symbol whose
5534 tree node is DECL to have the value of the tree node TARGET. */
5536 void
5537 do_assemble_alias (tree decl, tree target)
5539 /* Emulated TLS had better not get this var. */
5540 gcc_assert (!(!targetm.have_tls
5541 && TREE_CODE (decl) == VAR_DECL
5542 && DECL_THREAD_LOCAL_P (decl)));
5544 if (TREE_ASM_WRITTEN (decl))
5545 return;
5547 /* We must force creation of DECL_RTL for debug info generation, even though
5548 we don't use it here. */
5549 make_decl_rtl (decl);
5551 TREE_ASM_WRITTEN (decl) = 1;
5552 TREE_ASM_WRITTEN (DECL_ASSEMBLER_NAME (decl)) = 1;
5554 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5556 ultimate_transparent_alias_target (&target);
5558 if (!TREE_SYMBOL_REFERENCED (target))
5559 weakref_targets = tree_cons (decl, target, weakref_targets);
5561 #ifdef ASM_OUTPUT_WEAKREF
5562 ASM_OUTPUT_WEAKREF (asm_out_file, decl,
5563 IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5564 IDENTIFIER_POINTER (target));
5565 #else
5566 if (!TARGET_SUPPORTS_WEAK)
5568 error_at (DECL_SOURCE_LOCATION (decl),
5569 "weakref is not supported in this configuration");
5570 return;
5572 #endif
5573 return;
5576 #ifdef ASM_OUTPUT_DEF
5577 /* Make name accessible from other files, if appropriate. */
5579 if (TREE_PUBLIC (decl))
5581 globalize_decl (decl);
5582 maybe_assemble_visibility (decl);
5584 if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
5586 #if defined (ASM_OUTPUT_TYPE_DIRECTIVE)
5587 if (targetm.has_ifunc_p ())
5588 ASM_OUTPUT_TYPE_DIRECTIVE
5589 (asm_out_file, IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5590 IFUNC_ASM_TYPE);
5591 else
5592 #endif
5593 error_at (DECL_SOURCE_LOCATION (decl),
5594 "ifunc is not supported on this target");
5597 # ifdef ASM_OUTPUT_DEF_FROM_DECLS
5598 ASM_OUTPUT_DEF_FROM_DECLS (asm_out_file, decl, target);
5599 # else
5600 ASM_OUTPUT_DEF (asm_out_file,
5601 IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5602 IDENTIFIER_POINTER (target));
5603 # endif
5604 #elif defined (ASM_OUTPUT_WEAK_ALIAS) || defined (ASM_WEAKEN_DECL)
5606 const char *name;
5607 tree *p, t;
5609 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5610 # ifdef ASM_WEAKEN_DECL
5611 ASM_WEAKEN_DECL (asm_out_file, decl, name, IDENTIFIER_POINTER (target));
5612 # else
5613 ASM_OUTPUT_WEAK_ALIAS (asm_out_file, name, IDENTIFIER_POINTER (target));
5614 # endif
5615 /* Remove this function from the pending weak list so that
5616 we do not emit multiple .weak directives for it. */
5617 for (p = &weak_decls; (t = *p) ; )
5618 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5619 *p = TREE_CHAIN (t);
5620 else
5621 p = &TREE_CHAIN (t);
5623 /* Remove weakrefs to the same target from the pending weakref
5624 list, for the same reason. */
5625 for (p = &weakref_targets; (t = *p) ; )
5627 if (DECL_ASSEMBLER_NAME (decl)
5628 == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5629 *p = TREE_CHAIN (t);
5630 else
5631 p = &TREE_CHAIN (t);
5634 #endif
5637 /* Emit an assembler directive to make the symbol for DECL an alias to
5638 the symbol for TARGET. */
5640 void
5641 assemble_alias (tree decl, tree target)
5643 tree target_decl;
5645 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5647 tree alias = DECL_ASSEMBLER_NAME (decl);
5649 ultimate_transparent_alias_target (&target);
5651 if (alias == target)
5652 error ("weakref %q+D ultimately targets itself", decl);
5653 if (TREE_PUBLIC (decl))
5654 error ("weakref %q+D must have static linkage", decl);
5656 else
5658 #if !defined (ASM_OUTPUT_DEF)
5659 # if !defined(ASM_OUTPUT_WEAK_ALIAS) && !defined (ASM_WEAKEN_DECL)
5660 error_at (DECL_SOURCE_LOCATION (decl),
5661 "alias definitions not supported in this configuration");
5662 TREE_ASM_WRITTEN (decl) = 1;
5663 return;
5664 # else
5665 if (!DECL_WEAK (decl))
5667 if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
5668 error_at (DECL_SOURCE_LOCATION (decl),
5669 "ifunc is not supported in this configuration");
5670 else
5671 error_at (DECL_SOURCE_LOCATION (decl),
5672 "only weak aliases are supported in this configuration");
5673 TREE_ASM_WRITTEN (decl) = 1;
5674 return;
5676 # endif
5677 #endif
5679 TREE_USED (decl) = 1;
5681 /* Allow aliases to aliases. */
5682 if (TREE_CODE (decl) == FUNCTION_DECL)
5683 cgraph_get_create_node (decl)->alias = true;
5684 else
5685 varpool_node_for_decl (decl)->alias = true;
5687 /* If the target has already been emitted, we don't have to queue the
5688 alias. This saves a tad of memory. */
5689 if (cgraph_global_info_ready)
5690 target_decl = find_decl (target);
5691 else
5692 target_decl= NULL;
5693 if ((target_decl && TREE_ASM_WRITTEN (target_decl))
5694 || cgraph_state >= CGRAPH_STATE_EXPANSION)
5695 do_assemble_alias (decl, target);
5696 else
5698 alias_pair p = {decl, target};
5699 vec_safe_push (alias_pairs, p);
5703 /* Record and output a table of translations from original function
5704 to its transaction aware clone. Note that tm_pure functions are
5705 considered to be their own clone. */
5707 static GTY((if_marked ("tree_map_marked_p"), param_is (struct tree_map)))
5708 htab_t tm_clone_hash;
5710 void
5711 record_tm_clone_pair (tree o, tree n)
5713 struct tree_map **slot, *h;
5715 if (tm_clone_hash == NULL)
5716 tm_clone_hash = htab_create_ggc (32, tree_map_hash, tree_map_eq, 0);
5718 h = ggc_alloc<tree_map> ();
5719 h->hash = htab_hash_pointer (o);
5720 h->base.from = o;
5721 h->to = n;
5723 slot = (struct tree_map **)
5724 htab_find_slot_with_hash (tm_clone_hash, h, h->hash, INSERT);
5725 *slot = h;
5728 tree
5729 get_tm_clone_pair (tree o)
5731 if (tm_clone_hash)
5733 struct tree_map *h, in;
5735 in.base.from = o;
5736 in.hash = htab_hash_pointer (o);
5737 h = (struct tree_map *) htab_find_with_hash (tm_clone_hash,
5738 &in, in.hash);
5739 if (h)
5740 return h->to;
5742 return NULL_TREE;
5745 typedef struct tm_alias_pair
5747 unsigned int uid;
5748 tree from;
5749 tree to;
5750 } tm_alias_pair;
5753 /* Helper function for finish_tm_clone_pairs. Dump a hash table entry
5754 into a VEC in INFO. */
5756 static int
5757 dump_tm_clone_to_vec (void **slot, void *info)
5759 struct tree_map *map = (struct tree_map *) *slot;
5760 vec<tm_alias_pair> *tm_alias_pairs = (vec<tm_alias_pair> *) info;
5761 tm_alias_pair p = {DECL_UID (map->base.from), map->base.from, map->to};
5762 tm_alias_pairs->safe_push (p);
5763 return 1;
5766 /* Dump the actual pairs to the .tm_clone_table section. */
5768 static void
5769 dump_tm_clone_pairs (vec<tm_alias_pair> tm_alias_pairs)
5771 unsigned i;
5772 tm_alias_pair *p;
5773 bool switched = false;
5775 FOR_EACH_VEC_ELT (tm_alias_pairs, i, p)
5777 tree src = p->from;
5778 tree dst = p->to;
5779 struct cgraph_node *src_n = cgraph_get_node (src);
5780 struct cgraph_node *dst_n = cgraph_get_node (dst);
5782 /* The function ipa_tm_create_version() marks the clone as needed if
5783 the original function was needed. But we also mark the clone as
5784 needed if we ever called the clone indirectly through
5785 TM_GETTMCLONE. If neither of these are true, we didn't generate
5786 a clone, and we didn't call it indirectly... no sense keeping it
5787 in the clone table. */
5788 if (!dst_n || !dst_n->definition)
5789 continue;
5791 /* This covers the case where we have optimized the original
5792 function away, and only access the transactional clone. */
5793 if (!src_n || !src_n->definition)
5794 continue;
5796 if (!switched)
5798 switch_to_section (targetm.asm_out.tm_clone_table_section ());
5799 assemble_align (POINTER_SIZE);
5800 switched = true;
5803 assemble_integer (XEXP (DECL_RTL (src), 0),
5804 POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
5805 assemble_integer (XEXP (DECL_RTL (dst), 0),
5806 POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
5810 /* Provide a default for the tm_clone_table section. */
5812 section *
5813 default_clone_table_section (void)
5815 return get_named_section (NULL, ".tm_clone_table", 3);
5818 /* Helper comparison function for qsorting by the DECL_UID stored in
5819 alias_pair->emitted_diags. */
5821 static int
5822 tm_alias_pair_cmp (const void *x, const void *y)
5824 const tm_alias_pair *p1 = (const tm_alias_pair *) x;
5825 const tm_alias_pair *p2 = (const tm_alias_pair *) y;
5826 if (p1->uid < p2->uid)
5827 return -1;
5828 if (p1->uid > p2->uid)
5829 return 1;
5830 return 0;
5833 void
5834 finish_tm_clone_pairs (void)
5836 vec<tm_alias_pair> tm_alias_pairs = vNULL;
5838 if (tm_clone_hash == NULL)
5839 return;
5841 /* We need a determenistic order for the .tm_clone_table, otherwise
5842 we will get bootstrap comparison failures, so dump the hash table
5843 to a vector, sort it, and dump the vector. */
5845 /* Dump the hashtable to a vector. */
5846 htab_traverse_noresize (tm_clone_hash, dump_tm_clone_to_vec,
5847 (void *) &tm_alias_pairs);
5848 /* Sort it. */
5849 tm_alias_pairs.qsort (tm_alias_pair_cmp);
5851 /* Dump it. */
5852 dump_tm_clone_pairs (tm_alias_pairs);
5854 htab_delete (tm_clone_hash);
5855 tm_clone_hash = NULL;
5856 tm_alias_pairs.release ();
5860 /* Emit an assembler directive to set symbol for DECL visibility to
5861 the visibility type VIS, which must not be VISIBILITY_DEFAULT. */
5863 void
5864 default_assemble_visibility (tree decl ATTRIBUTE_UNUSED,
5865 int vis ATTRIBUTE_UNUSED)
5867 #ifdef HAVE_GAS_HIDDEN
5868 static const char * const visibility_types[] = {
5869 NULL, "protected", "hidden", "internal"
5872 const char *name, *type;
5874 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5875 type = visibility_types[vis];
5877 fprintf (asm_out_file, "\t.%s\t", type);
5878 assemble_name (asm_out_file, name);
5879 fprintf (asm_out_file, "\n");
5880 #else
5881 if (!DECL_ARTIFICIAL (decl))
5882 warning (OPT_Wattributes, "visibility attribute not supported "
5883 "in this configuration; ignored");
5884 #endif
5887 /* A helper function to call assemble_visibility when needed for a decl. */
5890 maybe_assemble_visibility (tree decl)
5892 enum symbol_visibility vis = DECL_VISIBILITY (decl);
5894 if (vis != VISIBILITY_DEFAULT)
5896 targetm.asm_out.assemble_visibility (decl, vis);
5897 return 1;
5899 else
5900 return 0;
5903 /* Returns 1 if the target configuration supports defining public symbols
5904 so that one of them will be chosen at link time instead of generating a
5905 multiply-defined symbol error, whether through the use of weak symbols or
5906 a target-specific mechanism for having duplicates discarded. */
5909 supports_one_only (void)
5911 if (SUPPORTS_ONE_ONLY)
5912 return 1;
5913 return TARGET_SUPPORTS_WEAK;
5916 /* Set up DECL as a public symbol that can be defined in multiple
5917 translation units without generating a linker error. */
5919 void
5920 make_decl_one_only (tree decl, tree comdat_group)
5922 struct symtab_node *symbol;
5923 gcc_assert (TREE_CODE (decl) == VAR_DECL
5924 || TREE_CODE (decl) == FUNCTION_DECL);
5926 TREE_PUBLIC (decl) = 1;
5928 if (TREE_CODE (decl) == VAR_DECL)
5929 symbol = varpool_node_for_decl (decl);
5930 else
5931 symbol = cgraph_get_create_node (decl);
5933 if (SUPPORTS_ONE_ONLY)
5935 #ifdef MAKE_DECL_ONE_ONLY
5936 MAKE_DECL_ONE_ONLY (decl);
5937 #endif
5938 symbol->set_comdat_group (comdat_group);
5940 else if (TREE_CODE (decl) == VAR_DECL
5941 && (DECL_INITIAL (decl) == 0 || DECL_INITIAL (decl) == error_mark_node))
5942 DECL_COMMON (decl) = 1;
5943 else
5945 gcc_assert (TARGET_SUPPORTS_WEAK);
5946 DECL_WEAK (decl) = 1;
5950 void
5951 init_varasm_once (void)
5953 section_htab = htab_create_ggc (31, section_entry_hash,
5954 section_entry_eq, NULL);
5955 object_block_htab = htab_create_ggc (31, object_block_entry_hash,
5956 object_block_entry_eq, NULL);
5957 const_desc_htab = htab_create_ggc (1009, const_desc_hash,
5958 const_desc_eq, NULL);
5960 const_alias_set = new_alias_set ();
5961 shared_constant_pool = create_constant_pool ();
5963 #ifdef TEXT_SECTION_ASM_OP
5964 text_section = get_unnamed_section (SECTION_CODE, output_section_asm_op,
5965 TEXT_SECTION_ASM_OP);
5966 #endif
5968 #ifdef DATA_SECTION_ASM_OP
5969 data_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
5970 DATA_SECTION_ASM_OP);
5971 #endif
5973 #ifdef SDATA_SECTION_ASM_OP
5974 sdata_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
5975 SDATA_SECTION_ASM_OP);
5976 #endif
5978 #ifdef READONLY_DATA_SECTION_ASM_OP
5979 readonly_data_section = get_unnamed_section (0, output_section_asm_op,
5980 READONLY_DATA_SECTION_ASM_OP);
5981 #endif
5983 #ifdef CTORS_SECTION_ASM_OP
5984 ctors_section = get_unnamed_section (0, output_section_asm_op,
5985 CTORS_SECTION_ASM_OP);
5986 #endif
5988 #ifdef DTORS_SECTION_ASM_OP
5989 dtors_section = get_unnamed_section (0, output_section_asm_op,
5990 DTORS_SECTION_ASM_OP);
5991 #endif
5993 #ifdef BSS_SECTION_ASM_OP
5994 bss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
5995 output_section_asm_op,
5996 BSS_SECTION_ASM_OP);
5997 #endif
5999 #ifdef SBSS_SECTION_ASM_OP
6000 sbss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
6001 output_section_asm_op,
6002 SBSS_SECTION_ASM_OP);
6003 #endif
6005 tls_comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6006 | SECTION_COMMON, emit_tls_common);
6007 lcomm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6008 | SECTION_COMMON, emit_local);
6009 comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6010 | SECTION_COMMON, emit_common);
6012 #if defined ASM_OUTPUT_ALIGNED_BSS
6013 bss_noswitch_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS,
6014 emit_bss);
6015 #endif
6017 targetm.asm_out.init_sections ();
6019 if (readonly_data_section == NULL)
6020 readonly_data_section = text_section;
6022 #ifdef ASM_OUTPUT_EXTERNAL
6023 pending_assemble_externals_set = pointer_set_create ();
6024 #endif
6027 enum tls_model
6028 decl_default_tls_model (const_tree decl)
6030 enum tls_model kind;
6031 bool is_local;
6033 is_local = targetm.binds_local_p (decl);
6034 if (!flag_shlib)
6036 if (is_local)
6037 kind = TLS_MODEL_LOCAL_EXEC;
6038 else
6039 kind = TLS_MODEL_INITIAL_EXEC;
6042 /* Local dynamic is inefficient when we're not combining the
6043 parts of the address. */
6044 else if (optimize && is_local)
6045 kind = TLS_MODEL_LOCAL_DYNAMIC;
6046 else
6047 kind = TLS_MODEL_GLOBAL_DYNAMIC;
6048 if (kind < flag_tls_default)
6049 kind = flag_tls_default;
6051 return kind;
6054 /* Select a set of attributes for section NAME based on the properties
6055 of DECL and whether or not RELOC indicates that DECL's initializer
6056 might contain runtime relocations.
6058 We make the section read-only and executable for a function decl,
6059 read-only for a const data decl, and writable for a non-const data decl. */
6061 unsigned int
6062 default_section_type_flags (tree decl, const char *name, int reloc)
6064 unsigned int flags;
6066 if (decl && TREE_CODE (decl) == FUNCTION_DECL)
6067 flags = SECTION_CODE;
6068 else if (decl)
6070 enum section_category category
6071 = categorize_decl_for_section (decl, reloc);
6072 if (decl_readonly_section_1 (category))
6073 flags = 0;
6074 else if (category == SECCAT_DATA_REL_RO
6075 || category == SECCAT_DATA_REL_RO_LOCAL)
6076 flags = SECTION_WRITE | SECTION_RELRO;
6077 else
6078 flags = SECTION_WRITE;
6080 else
6082 flags = SECTION_WRITE;
6083 if (strcmp (name, ".data.rel.ro") == 0
6084 || strcmp (name, ".data.rel.ro.local") == 0)
6085 flags |= SECTION_RELRO;
6088 if (decl && DECL_P (decl) && DECL_COMDAT_GROUP (decl))
6089 flags |= SECTION_LINKONCE;
6091 if (strcmp (name, ".vtable_map_vars") == 0)
6092 flags |= SECTION_LINKONCE;
6094 if (decl && TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6095 flags |= SECTION_TLS | SECTION_WRITE;
6097 if (strcmp (name, ".bss") == 0
6098 || strncmp (name, ".bss.", 5) == 0
6099 || strncmp (name, ".gnu.linkonce.b.", 16) == 0
6100 || strcmp (name, ".sbss") == 0
6101 || strncmp (name, ".sbss.", 6) == 0
6102 || strncmp (name, ".gnu.linkonce.sb.", 17) == 0)
6103 flags |= SECTION_BSS;
6105 if (strcmp (name, ".tdata") == 0
6106 || strncmp (name, ".tdata.", 7) == 0
6107 || strncmp (name, ".gnu.linkonce.td.", 17) == 0)
6108 flags |= SECTION_TLS;
6110 if (strcmp (name, ".tbss") == 0
6111 || strncmp (name, ".tbss.", 6) == 0
6112 || strncmp (name, ".gnu.linkonce.tb.", 17) == 0)
6113 flags |= SECTION_TLS | SECTION_BSS;
6115 /* These three sections have special ELF types. They are neither
6116 SHT_PROGBITS nor SHT_NOBITS, so when changing sections we don't
6117 want to print a section type (@progbits or @nobits). If someone
6118 is silly enough to emit code or TLS variables to one of these
6119 sections, then don't handle them specially. */
6120 if (!(flags & (SECTION_CODE | SECTION_BSS | SECTION_TLS))
6121 && (strcmp (name, ".init_array") == 0
6122 || strcmp (name, ".fini_array") == 0
6123 || strcmp (name, ".preinit_array") == 0))
6124 flags |= SECTION_NOTYPE;
6126 #ifdef UPC_SHARED_SECTION_NAME
6127 /* The UPC shared section is not loaded into memory.
6128 It is used only to layout shared veriables. */
6129 if (!(flags & (SECTION_CODE | SECTION_BSS | SECTION_TLS))
6130 && (strcmp (name, UPC_SHARED_SECTION_NAME) == 0))
6132 flags |= SECTION_BSS;
6133 # ifdef HAVE_UPC_LINK_SCRIPT
6134 flags = SECTION_DEBUG | (flags & ~SECTION_WRITE);
6135 # endif
6137 #endif
6139 return flags;
6142 /* Return true if the target supports some form of global BSS,
6143 either through bss_noswitch_section, or by selecting a BSS
6144 section in TARGET_ASM_SELECT_SECTION. */
6146 bool
6147 have_global_bss_p (void)
6149 return bss_noswitch_section || targetm.have_switchable_bss_sections;
6152 /* Output assembly to switch to section NAME with attribute FLAGS.
6153 Four variants for common object file formats. */
6155 void
6156 default_no_named_section (const char *name ATTRIBUTE_UNUSED,
6157 unsigned int flags ATTRIBUTE_UNUSED,
6158 tree decl ATTRIBUTE_UNUSED)
6160 /* Some object formats don't support named sections at all. The
6161 front-end should already have flagged this as an error. */
6162 gcc_unreachable ();
6165 #ifndef TLS_SECTION_ASM_FLAG
6166 #define TLS_SECTION_ASM_FLAG 'T'
6167 #endif
6169 void
6170 default_elf_asm_named_section (const char *name, unsigned int flags,
6171 tree decl ATTRIBUTE_UNUSED)
6173 char flagchars[10], *f = flagchars;
6175 /* If we have already declared this section, we can use an
6176 abbreviated form to switch back to it -- unless this section is
6177 part of a COMDAT groups, in which case GAS requires the full
6178 declaration every time. */
6179 if (!(HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6180 && (flags & SECTION_DECLARED))
6182 fprintf (asm_out_file, "\t.section\t%s\n", name);
6183 return;
6186 if (!(flags & SECTION_DEBUG))
6187 *f++ = 'a';
6188 if (flags & SECTION_EXCLUDE)
6189 *f++ = 'e';
6190 if (flags & SECTION_WRITE)
6191 *f++ = 'w';
6192 if (flags & SECTION_CODE)
6193 *f++ = 'x';
6194 if (flags & SECTION_SMALL)
6195 *f++ = 's';
6196 if (flags & SECTION_MERGE)
6197 *f++ = 'M';
6198 if (flags & SECTION_STRINGS)
6199 *f++ = 'S';
6200 if (flags & SECTION_TLS)
6201 *f++ = TLS_SECTION_ASM_FLAG;
6202 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6203 *f++ = 'G';
6204 *f = '\0';
6206 fprintf (asm_out_file, "\t.section\t%s,\"%s\"", name, flagchars);
6208 if (!(flags & SECTION_NOTYPE))
6210 const char *type;
6211 const char *format;
6213 if (flags & SECTION_BSS)
6214 type = "nobits";
6215 else
6216 type = "progbits";
6218 format = ",@%s";
6219 /* On platforms that use "@" as the assembly comment character,
6220 use "%" instead. */
6221 if (strcmp (ASM_COMMENT_START, "@") == 0)
6222 format = ",%%%s";
6223 fprintf (asm_out_file, format, type);
6225 if (flags & SECTION_ENTSIZE)
6226 fprintf (asm_out_file, ",%d", flags & SECTION_ENTSIZE);
6227 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6229 if (TREE_CODE (decl) == IDENTIFIER_NODE)
6230 fprintf (asm_out_file, ",%s,comdat", IDENTIFIER_POINTER (decl));
6231 else
6232 fprintf (asm_out_file, ",%s,comdat",
6233 IDENTIFIER_POINTER (DECL_COMDAT_GROUP (decl)));
6237 putc ('\n', asm_out_file);
6240 void
6241 default_coff_asm_named_section (const char *name, unsigned int flags,
6242 tree decl ATTRIBUTE_UNUSED)
6244 char flagchars[8], *f = flagchars;
6246 if (flags & SECTION_WRITE)
6247 *f++ = 'w';
6248 if (flags & SECTION_CODE)
6249 *f++ = 'x';
6250 *f = '\0';
6252 fprintf (asm_out_file, "\t.section\t%s,\"%s\"\n", name, flagchars);
6255 void
6256 default_pe_asm_named_section (const char *name, unsigned int flags,
6257 tree decl)
6259 default_coff_asm_named_section (name, flags, decl);
6261 if (flags & SECTION_LINKONCE)
6263 /* Functions may have been compiled at various levels of
6264 optimization so we can't use `same_size' here.
6265 Instead, have the linker pick one. */
6266 fprintf (asm_out_file, "\t.linkonce %s\n",
6267 (flags & SECTION_CODE ? "discard" : "same_size"));
6271 /* The lame default section selector. */
6273 section *
6274 default_select_section (tree decl, int reloc,
6275 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6277 if (DECL_P (decl))
6279 if (decl_readonly_section (decl, reloc))
6280 return readonly_data_section;
6282 else if (TREE_CODE (decl) == CONSTRUCTOR)
6284 if (! ((flag_pic && reloc)
6285 || !TREE_READONLY (decl)
6286 || TREE_SIDE_EFFECTS (decl)
6287 || !TREE_CONSTANT (decl)))
6288 return readonly_data_section;
6290 else if (TREE_CODE (decl) == STRING_CST)
6291 return readonly_data_section;
6292 else if (! (flag_pic && reloc))
6293 return readonly_data_section;
6295 return data_section;
6298 enum section_category
6299 categorize_decl_for_section (const_tree decl, int reloc)
6301 enum section_category ret;
6303 if (TREE_CODE (decl) == FUNCTION_DECL)
6304 return SECCAT_TEXT;
6305 else if (TREE_CODE (decl) == STRING_CST)
6307 if ((flag_sanitize & SANITIZE_ADDRESS)
6308 && asan_protect_global (CONST_CAST_TREE (decl)))
6309 /* or !flag_merge_constants */
6310 return SECCAT_RODATA;
6311 else
6312 return SECCAT_RODATA_MERGE_STR;
6314 else if (TREE_CODE (decl) == VAR_DECL)
6316 if (bss_initializer_p (decl))
6317 ret = SECCAT_BSS;
6318 else if (! TREE_READONLY (decl)
6319 || TREE_SIDE_EFFECTS (decl)
6320 || ! TREE_CONSTANT (DECL_INITIAL (decl)))
6322 /* Here the reloc_rw_mask is not testing whether the section should
6323 be read-only or not, but whether the dynamic link will have to
6324 do something. If so, we wish to segregate the data in order to
6325 minimize cache misses inside the dynamic linker. */
6326 if (reloc & targetm.asm_out.reloc_rw_mask ())
6327 ret = reloc == 1 ? SECCAT_DATA_REL_LOCAL : SECCAT_DATA_REL;
6328 else
6329 ret = SECCAT_DATA;
6331 else if (reloc & targetm.asm_out.reloc_rw_mask ())
6332 ret = reloc == 1 ? SECCAT_DATA_REL_RO_LOCAL : SECCAT_DATA_REL_RO;
6333 else if (reloc || flag_merge_constants < 2
6334 || ((flag_sanitize & SANITIZE_ADDRESS)
6335 && asan_protect_global (CONST_CAST_TREE (decl))))
6336 /* C and C++ don't allow different variables to share the same
6337 location. -fmerge-all-constants allows even that (at the
6338 expense of not conforming). */
6339 ret = SECCAT_RODATA;
6340 else if (TREE_CODE (DECL_INITIAL (decl)) == STRING_CST)
6341 ret = SECCAT_RODATA_MERGE_STR_INIT;
6342 else
6343 ret = SECCAT_RODATA_MERGE_CONST;
6345 else if (TREE_CODE (decl) == CONSTRUCTOR)
6347 if ((reloc & targetm.asm_out.reloc_rw_mask ())
6348 || TREE_SIDE_EFFECTS (decl)
6349 || ! TREE_CONSTANT (decl))
6350 ret = SECCAT_DATA;
6351 else
6352 ret = SECCAT_RODATA;
6354 else
6355 ret = SECCAT_RODATA;
6357 /* There are no read-only thread-local sections. */
6358 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6360 /* Note that this would be *just* SECCAT_BSS, except that there's
6361 no concept of a read-only thread-local-data section. */
6362 if (ret == SECCAT_BSS
6363 || (flag_zero_initialized_in_bss
6364 && initializer_zerop (DECL_INITIAL (decl))))
6365 ret = SECCAT_TBSS;
6366 else
6367 ret = SECCAT_TDATA;
6370 /* If the target uses small data sections, select it. */
6371 else if (targetm.in_small_data_p (decl))
6373 if (ret == SECCAT_BSS)
6374 ret = SECCAT_SBSS;
6375 else if (targetm.have_srodata_section && ret == SECCAT_RODATA)
6376 ret = SECCAT_SRODATA;
6377 else
6378 ret = SECCAT_SDATA;
6381 return ret;
6384 static bool
6385 decl_readonly_section_1 (enum section_category category)
6387 switch (category)
6389 case SECCAT_RODATA:
6390 case SECCAT_RODATA_MERGE_STR:
6391 case SECCAT_RODATA_MERGE_STR_INIT:
6392 case SECCAT_RODATA_MERGE_CONST:
6393 case SECCAT_SRODATA:
6394 return true;
6395 default:
6396 return false;
6400 bool
6401 decl_readonly_section (const_tree decl, int reloc)
6403 return decl_readonly_section_1 (categorize_decl_for_section (decl, reloc));
6406 /* Select a section based on the above categorization. */
6408 section *
6409 default_elf_select_section (tree decl, int reloc,
6410 unsigned HOST_WIDE_INT align)
6412 const char *sname;
6413 switch (categorize_decl_for_section (decl, reloc))
6415 case SECCAT_TEXT:
6416 /* We're not supposed to be called on FUNCTION_DECLs. */
6417 gcc_unreachable ();
6418 case SECCAT_RODATA:
6419 return readonly_data_section;
6420 case SECCAT_RODATA_MERGE_STR:
6421 return mergeable_string_section (decl, align, 0);
6422 case SECCAT_RODATA_MERGE_STR_INIT:
6423 return mergeable_string_section (DECL_INITIAL (decl), align, 0);
6424 case SECCAT_RODATA_MERGE_CONST:
6425 return mergeable_constant_section (DECL_MODE (decl), align, 0);
6426 case SECCAT_SRODATA:
6427 sname = ".sdata2";
6428 break;
6429 case SECCAT_DATA:
6430 return data_section;
6431 case SECCAT_DATA_REL:
6432 sname = ".data.rel";
6433 break;
6434 case SECCAT_DATA_REL_LOCAL:
6435 sname = ".data.rel.local";
6436 break;
6437 case SECCAT_DATA_REL_RO:
6438 sname = ".data.rel.ro";
6439 break;
6440 case SECCAT_DATA_REL_RO_LOCAL:
6441 sname = ".data.rel.ro.local";
6442 break;
6443 case SECCAT_SDATA:
6444 sname = ".sdata";
6445 break;
6446 case SECCAT_TDATA:
6447 sname = ".tdata";
6448 break;
6449 case SECCAT_BSS:
6450 if (bss_section)
6451 return bss_section;
6452 sname = ".bss";
6453 break;
6454 case SECCAT_SBSS:
6455 sname = ".sbss";
6456 break;
6457 case SECCAT_TBSS:
6458 sname = ".tbss";
6459 break;
6460 default:
6461 gcc_unreachable ();
6464 return get_named_section (decl, sname, reloc);
6467 /* Construct a unique section name based on the decl name and the
6468 categorization performed above. */
6470 void
6471 default_unique_section (tree decl, int reloc)
6473 /* We only need to use .gnu.linkonce if we don't have COMDAT groups. */
6474 bool one_only = DECL_ONE_ONLY (decl) && !HAVE_COMDAT_GROUP;
6475 const char *prefix, *name, *linkonce;
6476 char *string;
6478 switch (categorize_decl_for_section (decl, reloc))
6480 case SECCAT_TEXT:
6481 prefix = one_only ? ".t" : ".text";
6482 break;
6483 case SECCAT_RODATA:
6484 case SECCAT_RODATA_MERGE_STR:
6485 case SECCAT_RODATA_MERGE_STR_INIT:
6486 case SECCAT_RODATA_MERGE_CONST:
6487 prefix = one_only ? ".r" : ".rodata";
6488 break;
6489 case SECCAT_SRODATA:
6490 prefix = one_only ? ".s2" : ".sdata2";
6491 break;
6492 case SECCAT_DATA:
6493 prefix = one_only ? ".d" : ".data";
6494 break;
6495 case SECCAT_DATA_REL:
6496 prefix = one_only ? ".d.rel" : ".data.rel";
6497 break;
6498 case SECCAT_DATA_REL_LOCAL:
6499 prefix = one_only ? ".d.rel.local" : ".data.rel.local";
6500 break;
6501 case SECCAT_DATA_REL_RO:
6502 prefix = one_only ? ".d.rel.ro" : ".data.rel.ro";
6503 break;
6504 case SECCAT_DATA_REL_RO_LOCAL:
6505 prefix = one_only ? ".d.rel.ro.local" : ".data.rel.ro.local";
6506 break;
6507 case SECCAT_SDATA:
6508 prefix = one_only ? ".s" : ".sdata";
6509 break;
6510 case SECCAT_BSS:
6511 prefix = one_only ? ".b" : ".bss";
6512 break;
6513 case SECCAT_SBSS:
6514 prefix = one_only ? ".sb" : ".sbss";
6515 break;
6516 case SECCAT_TDATA:
6517 prefix = one_only ? ".td" : ".tdata";
6518 break;
6519 case SECCAT_TBSS:
6520 prefix = one_only ? ".tb" : ".tbss";
6521 break;
6522 default:
6523 gcc_unreachable ();
6526 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
6527 name = targetm.strip_name_encoding (name);
6529 /* If we're using one_only, then there needs to be a .gnu.linkonce
6530 prefix to the section name. */
6531 linkonce = one_only ? ".gnu.linkonce" : "";
6533 string = ACONCAT ((linkonce, prefix, ".", name, NULL));
6535 DECL_SECTION_NAME (decl) = build_string (strlen (string), string);
6538 /* Like compute_reloc_for_constant, except for an RTX. The return value
6539 is a mask for which bit 1 indicates a global relocation, and bit 0
6540 indicates a local relocation. */
6542 static int
6543 compute_reloc_for_rtx_1 (rtx *xp, void *data)
6545 int *preloc = (int *) data;
6546 rtx x = *xp;
6548 switch (GET_CODE (x))
6550 case SYMBOL_REF:
6551 *preloc |= SYMBOL_REF_LOCAL_P (x) ? 1 : 2;
6552 break;
6553 case LABEL_REF:
6554 *preloc |= 1;
6555 break;
6556 default:
6557 break;
6560 return 0;
6563 static int
6564 compute_reloc_for_rtx (rtx x)
6566 int reloc;
6568 switch (GET_CODE (x))
6570 case CONST:
6571 case SYMBOL_REF:
6572 case LABEL_REF:
6573 reloc = 0;
6574 for_each_rtx (&x, compute_reloc_for_rtx_1, &reloc);
6575 return reloc;
6577 default:
6578 return 0;
6582 section *
6583 default_select_rtx_section (enum machine_mode mode ATTRIBUTE_UNUSED,
6584 rtx x,
6585 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6587 if (compute_reloc_for_rtx (x) & targetm.asm_out.reloc_rw_mask ())
6588 return data_section;
6589 else
6590 return readonly_data_section;
6593 section *
6594 default_elf_select_rtx_section (enum machine_mode mode, rtx x,
6595 unsigned HOST_WIDE_INT align)
6597 int reloc = compute_reloc_for_rtx (x);
6599 /* ??? Handle small data here somehow. */
6601 if (reloc & targetm.asm_out.reloc_rw_mask ())
6603 if (reloc == 1)
6604 return get_named_section (NULL, ".data.rel.ro.local", 1);
6605 else
6606 return get_named_section (NULL, ".data.rel.ro", 3);
6609 return mergeable_constant_section (mode, align, 0);
6612 /* Set the generally applicable flags on the SYMBOL_REF for EXP. */
6614 void
6615 default_encode_section_info (tree decl, rtx rtl, int first ATTRIBUTE_UNUSED)
6617 rtx symbol;
6618 int flags;
6620 /* Careful not to prod global register variables. */
6621 if (!MEM_P (rtl))
6622 return;
6623 symbol = XEXP (rtl, 0);
6624 if (GET_CODE (symbol) != SYMBOL_REF)
6625 return;
6627 flags = SYMBOL_REF_FLAGS (symbol) & SYMBOL_FLAG_HAS_BLOCK_INFO;
6628 if (TREE_CODE (decl) == FUNCTION_DECL)
6629 flags |= SYMBOL_FLAG_FUNCTION;
6630 if (targetm.binds_local_p (decl))
6631 flags |= SYMBOL_FLAG_LOCAL;
6632 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6633 flags |= DECL_TLS_MODEL (decl) << SYMBOL_FLAG_TLS_SHIFT;
6634 else if (targetm.in_small_data_p (decl))
6635 flags |= SYMBOL_FLAG_SMALL;
6636 /* ??? Why is DECL_EXTERNAL ever set for non-PUBLIC names? Without
6637 being PUBLIC, the thing *must* be defined in this translation unit.
6638 Prevent this buglet from being propagated into rtl code as well. */
6639 if (DECL_P (decl) && DECL_EXTERNAL (decl) && TREE_PUBLIC (decl))
6640 flags |= SYMBOL_FLAG_EXTERNAL;
6642 SYMBOL_REF_FLAGS (symbol) = flags;
6645 /* By default, we do nothing for encode_section_info, so we need not
6646 do anything but discard the '*' marker. */
6648 const char *
6649 default_strip_name_encoding (const char *str)
6651 return str + (*str == '*');
6654 #ifdef ASM_OUTPUT_DEF
6655 /* The default implementation of TARGET_ASM_OUTPUT_ANCHOR. Define the
6656 anchor relative to ".", the current section position. */
6658 void
6659 default_asm_output_anchor (rtx symbol)
6661 char buffer[100];
6663 sprintf (buffer, "*. + " HOST_WIDE_INT_PRINT_DEC,
6664 SYMBOL_REF_BLOCK_OFFSET (symbol));
6665 ASM_OUTPUT_DEF (asm_out_file, XSTR (symbol, 0), buffer);
6667 #endif
6669 /* The default implementation of TARGET_USE_ANCHORS_FOR_SYMBOL_P. */
6671 bool
6672 default_use_anchors_for_symbol_p (const_rtx symbol)
6674 section *sect;
6675 tree decl;
6677 /* Don't use anchors for mergeable sections. The linker might move
6678 the objects around. */
6679 sect = SYMBOL_REF_BLOCK (symbol)->sect;
6680 if (sect->common.flags & SECTION_MERGE)
6681 return false;
6683 /* Don't use anchors for small data sections. The small data register
6684 acts as an anchor for such sections. */
6685 if (sect->common.flags & SECTION_SMALL)
6686 return false;
6688 decl = SYMBOL_REF_DECL (symbol);
6689 if (decl && DECL_P (decl))
6691 /* Don't use section anchors for decls that might be defined or
6692 usurped by other modules. */
6693 if (TREE_PUBLIC (decl) && !decl_binds_to_current_def_p (decl))
6694 return false;
6696 /* Don't use section anchors for decls that will be placed in a
6697 small data section. */
6698 /* ??? Ideally, this check would be redundant with the SECTION_SMALL
6699 one above. The problem is that we only use SECTION_SMALL for
6700 sections that should be marked as small in the section directive. */
6701 if (targetm.in_small_data_p (decl))
6702 return false;
6704 return true;
6707 /* Return true when RESOLUTION indicate that symbol will be bound to the
6708 definition provided by current .o file. */
6710 static bool
6711 resolution_to_local_definition_p (enum ld_plugin_symbol_resolution resolution)
6713 return (resolution == LDPR_PREVAILING_DEF
6714 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
6715 || resolution == LDPR_PREVAILING_DEF_IRONLY);
6718 /* Return true when RESOLUTION indicate that symbol will be bound locally
6719 within current executable or DSO. */
6721 static bool
6722 resolution_local_p (enum ld_plugin_symbol_resolution resolution)
6724 return (resolution == LDPR_PREVAILING_DEF
6725 || resolution == LDPR_PREVAILING_DEF_IRONLY
6726 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
6727 || resolution == LDPR_PREEMPTED_REG
6728 || resolution == LDPR_PREEMPTED_IR
6729 || resolution == LDPR_RESOLVED_IR
6730 || resolution == LDPR_RESOLVED_EXEC);
6733 /* Assume ELF-ish defaults, since that's pretty much the most liberal
6734 wrt cross-module name binding. */
6736 bool
6737 default_binds_local_p (const_tree exp)
6739 return default_binds_local_p_1 (exp, flag_shlib);
6742 bool
6743 default_binds_local_p_1 (const_tree exp, int shlib)
6745 bool local_p;
6746 bool resolved_locally = false;
6747 bool resolved_to_local_def = false;
6749 /* With resolution file in hands, take look into resolutions.
6750 We can't just return true for resolved_locally symbols,
6751 because dynamic linking might overwrite symbols
6752 in shared libraries. */
6753 if (TREE_CODE (exp) == VAR_DECL && TREE_PUBLIC (exp)
6754 && (TREE_STATIC (exp) || DECL_EXTERNAL (exp)))
6756 varpool_node *vnode = varpool_get_node (exp);
6757 if (vnode && (resolution_local_p (vnode->resolution) || vnode->in_other_partition))
6758 resolved_locally = true;
6759 if (vnode
6760 && resolution_to_local_definition_p (vnode->resolution))
6761 resolved_to_local_def = true;
6763 else if (TREE_CODE (exp) == FUNCTION_DECL && TREE_PUBLIC (exp))
6765 struct cgraph_node *node = cgraph_get_node (exp);
6766 if (node
6767 && (resolution_local_p (node->resolution) || node->in_other_partition))
6768 resolved_locally = true;
6769 if (node
6770 && resolution_to_local_definition_p (node->resolution))
6771 resolved_to_local_def = true;
6774 /* A non-decl is an entry in the constant pool. */
6775 if (!DECL_P (exp))
6776 local_p = true;
6777 /* Weakrefs may not bind locally, even though the weakref itself is always
6778 static and therefore local. Similarly, the resolver for ifunc functions
6779 might resolve to a non-local function.
6780 FIXME: We can resolve the weakref case more curefuly by looking at the
6781 weakref alias. */
6782 else if (lookup_attribute ("weakref", DECL_ATTRIBUTES (exp))
6783 || (TREE_CODE (exp) == FUNCTION_DECL
6784 && lookup_attribute ("ifunc", DECL_ATTRIBUTES (exp))))
6785 local_p = false;
6786 /* Static variables are always local. */
6787 else if (! TREE_PUBLIC (exp))
6788 local_p = true;
6789 /* A variable is local if the user has said explicitly that it will
6790 be. */
6791 else if ((DECL_VISIBILITY_SPECIFIED (exp)
6792 || resolved_to_local_def)
6793 && DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
6794 local_p = true;
6795 /* Variables defined outside this object might not be local. */
6796 else if (DECL_EXTERNAL (exp) && !resolved_locally)
6797 local_p = false;
6798 /* If defined in this object and visibility is not default, must be
6799 local. */
6800 else if (DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
6801 local_p = true;
6802 /* Default visibility weak data can be overridden by a strong symbol
6803 in another module and so are not local. */
6804 else if (DECL_WEAK (exp)
6805 && !resolved_locally)
6806 local_p = false;
6807 /* If PIC, then assume that any global name can be overridden by
6808 symbols resolved from other modules. */
6809 else if (shlib)
6810 local_p = false;
6811 /* Uninitialized COMMON variable may be unified with symbols
6812 resolved from other modules. */
6813 else if (DECL_COMMON (exp)
6814 && !resolved_locally
6815 && (DECL_INITIAL (exp) == NULL
6816 || DECL_INITIAL (exp) == error_mark_node))
6817 local_p = false;
6818 /* Otherwise we're left with initialized (or non-common) global data
6819 which is of necessity defined locally. */
6820 else
6821 local_p = true;
6823 return local_p;
6826 /* Return true when references to DECL must bind to current definition in
6827 final executable.
6829 The condition is usually equivalent to whether the function binds to the
6830 current module (shared library or executable), that is to binds_local_p.
6831 We use this fact to avoid need for another target hook and implement
6832 the logic using binds_local_p and just special cases where
6833 decl_binds_to_current_def_p is stronger than binds_local_p. In particular
6834 the weak definitions (that can be overwritten at linktime by other
6835 definition from different object file) and when resolution info is available
6836 we simply use the knowledge passed to us by linker plugin. */
6837 bool
6838 decl_binds_to_current_def_p (tree decl)
6840 gcc_assert (DECL_P (decl));
6841 if (!targetm.binds_local_p (decl))
6842 return false;
6843 if (!TREE_PUBLIC (decl))
6844 return true;
6845 /* When resolution is available, just use it. */
6846 if (TREE_CODE (decl) == VAR_DECL
6847 && (TREE_STATIC (decl) || DECL_EXTERNAL (decl)))
6849 varpool_node *vnode = varpool_get_node (decl);
6850 if (vnode
6851 && vnode->resolution != LDPR_UNKNOWN)
6852 return resolution_to_local_definition_p (vnode->resolution);
6854 else if (TREE_CODE (decl) == FUNCTION_DECL)
6856 struct cgraph_node *node = cgraph_get_node (decl);
6857 if (node
6858 && node->resolution != LDPR_UNKNOWN)
6859 return resolution_to_local_definition_p (node->resolution);
6861 /* Otherwise we have to assume the worst for DECL_WEAK (hidden weaks
6862 binds locally but still can be overwritten), DECL_COMMON (can be merged
6863 with a non-common definition somewhere in the same module) or
6864 DECL_EXTERNAL.
6865 This rely on fact that binds_local_p behave as decl_replaceable_p
6866 for all other declaration types. */
6867 if (DECL_WEAK (decl))
6868 return false;
6869 if (DECL_COMMON (decl)
6870 && (DECL_INITIAL (decl) == NULL
6871 || DECL_INITIAL (decl) == error_mark_node))
6872 return false;
6873 if (DECL_EXTERNAL (decl))
6874 return false;
6875 return true;
6878 /* A replaceable function or variable is one which may be replaced
6879 at link-time with an entirely different definition, provided that the
6880 replacement has the same type. For example, functions declared
6881 with __attribute__((weak)) on most systems are replaceable.
6883 COMDAT functions are not replaceable, since all definitions of the
6884 function must be equivalent. It is important that COMDAT functions
6885 not be treated as replaceable so that use of C++ template
6886 instantiations is not penalized. */
6888 bool
6889 decl_replaceable_p (tree decl)
6891 gcc_assert (DECL_P (decl));
6892 if (!TREE_PUBLIC (decl) || DECL_COMDAT (decl))
6893 return false;
6894 return !decl_binds_to_current_def_p (decl);
6897 /* Default function to output code that will globalize a label. A
6898 target must define GLOBAL_ASM_OP or provide its own function to
6899 globalize a label. */
6900 #ifdef GLOBAL_ASM_OP
6901 void
6902 default_globalize_label (FILE * stream, const char *name)
6904 fputs (GLOBAL_ASM_OP, stream);
6905 assemble_name (stream, name);
6906 putc ('\n', stream);
6908 #endif /* GLOBAL_ASM_OP */
6910 /* Default function to output code that will globalize a declaration. */
6911 void
6912 default_globalize_decl_name (FILE * stream, tree decl)
6914 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
6915 targetm.asm_out.globalize_label (stream, name);
6918 /* Default function to output a label for unwind information. The
6919 default is to do nothing. A target that needs nonlocal labels for
6920 unwind information must provide its own function to do this. */
6921 void
6922 default_emit_unwind_label (FILE * stream ATTRIBUTE_UNUSED,
6923 tree decl ATTRIBUTE_UNUSED,
6924 int for_eh ATTRIBUTE_UNUSED,
6925 int empty ATTRIBUTE_UNUSED)
6929 /* Default function to output a label to divide up the exception table.
6930 The default is to do nothing. A target that needs/wants to divide
6931 up the table must provide it's own function to do this. */
6932 void
6933 default_emit_except_table_label (FILE * stream ATTRIBUTE_UNUSED)
6937 /* This is how to output an internal numbered label where PREFIX is
6938 the class of label and LABELNO is the number within the class. */
6940 void
6941 default_generate_internal_label (char *buf, const char *prefix,
6942 unsigned long labelno)
6944 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
6947 /* This is how to output an internal numbered label where PREFIX is
6948 the class of label and LABELNO is the number within the class. */
6950 void
6951 default_internal_label (FILE *stream, const char *prefix,
6952 unsigned long labelno)
6954 char *const buf = (char *) alloca (40 + strlen (prefix));
6955 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
6956 ASM_OUTPUT_INTERNAL_LABEL (stream, buf);
6960 /* The default implementation of ASM_DECLARE_CONSTANT_NAME. */
6962 void
6963 default_asm_declare_constant_name (FILE *file, const char *name,
6964 const_tree exp ATTRIBUTE_UNUSED,
6965 HOST_WIDE_INT size ATTRIBUTE_UNUSED)
6967 assemble_label (file, name);
6970 /* This is the default behavior at the beginning of a file. It's
6971 controlled by two other target-hook toggles. */
6972 void
6973 default_file_start (void)
6975 if (targetm.asm_file_start_app_off
6976 && !(flag_verbose_asm || flag_debug_asm || flag_dump_rtl_in_asm))
6977 fputs (ASM_APP_OFF, asm_out_file);
6979 if (targetm.asm_file_start_file_directive)
6980 output_file_directive (asm_out_file, main_input_filename);
6983 /* This is a generic routine suitable for use as TARGET_ASM_FILE_END
6984 which emits a special section directive used to indicate whether or
6985 not this object file needs an executable stack. This is primarily
6986 a GNU extension to ELF but could be used on other targets. */
6988 int trampolines_created;
6990 void
6991 file_end_indicate_exec_stack (void)
6993 unsigned int flags = SECTION_DEBUG;
6994 if (trampolines_created)
6995 flags |= SECTION_CODE;
6997 switch_to_section (get_section (".note.GNU-stack", flags, NULL));
7000 /* Emit a special section directive to indicate that this object file
7001 was compiled with -fsplit-stack. This is used to let the linker
7002 detect calls between split-stack code and non-split-stack code, so
7003 that it can modify the split-stack code to allocate a sufficiently
7004 large stack. We emit another special section if there are any
7005 functions in this file which have the no_split_stack attribute, to
7006 prevent the linker from warning about being unable to convert the
7007 functions if they call non-split-stack code. */
7009 void
7010 file_end_indicate_split_stack (void)
7012 if (flag_split_stack)
7014 switch_to_section (get_section (".note.GNU-split-stack", SECTION_DEBUG,
7015 NULL));
7016 if (saw_no_split_stack)
7017 switch_to_section (get_section (".note.GNU-no-split-stack",
7018 SECTION_DEBUG, NULL));
7022 /* Output DIRECTIVE (a C string) followed by a newline. This is used as
7023 a get_unnamed_section callback. */
7025 void
7026 output_section_asm_op (const void *directive)
7028 fprintf (asm_out_file, "%s\n", (const char *) directive);
7031 /* Emit assembly code to switch to section NEW_SECTION. Do nothing if
7032 the current section is NEW_SECTION. */
7034 void
7035 switch_to_section (section *new_section)
7037 if (in_section == new_section)
7038 return;
7040 if (new_section->common.flags & SECTION_FORGET)
7041 in_section = NULL;
7042 else
7043 in_section = new_section;
7045 switch (SECTION_STYLE (new_section))
7047 case SECTION_NAMED:
7048 targetm.asm_out.named_section (new_section->named.name,
7049 new_section->named.common.flags,
7050 new_section->named.decl);
7051 break;
7053 case SECTION_UNNAMED:
7054 new_section->unnamed.callback (new_section->unnamed.data);
7055 break;
7057 case SECTION_NOSWITCH:
7058 gcc_unreachable ();
7059 break;
7062 new_section->common.flags |= SECTION_DECLARED;
7065 /* If block symbol SYMBOL has not yet been assigned an offset, place
7066 it at the end of its block. */
7068 void
7069 place_block_symbol (rtx symbol)
7071 unsigned HOST_WIDE_INT size, mask, offset;
7072 struct constant_descriptor_rtx *desc;
7073 unsigned int alignment;
7074 struct object_block *block;
7075 tree decl;
7077 gcc_assert (SYMBOL_REF_BLOCK (symbol));
7078 if (SYMBOL_REF_BLOCK_OFFSET (symbol) >= 0)
7079 return;
7081 /* Work out the symbol's size and alignment. */
7082 if (CONSTANT_POOL_ADDRESS_P (symbol))
7084 desc = SYMBOL_REF_CONSTANT (symbol);
7085 alignment = desc->align;
7086 size = GET_MODE_SIZE (desc->mode);
7088 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7090 decl = SYMBOL_REF_DECL (symbol);
7091 alignment = DECL_ALIGN (decl);
7092 size = get_constant_size (DECL_INITIAL (decl));
7093 if ((flag_sanitize & SANITIZE_ADDRESS)
7094 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
7095 && asan_protect_global (DECL_INITIAL (decl)))
7096 size += asan_red_zone_size (size);
7098 else
7100 decl = SYMBOL_REF_DECL (symbol);
7101 alignment = get_variable_align (decl);
7102 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
7103 if ((flag_sanitize & SANITIZE_ADDRESS)
7104 && asan_protect_global (decl))
7106 size += asan_red_zone_size (size);
7107 alignment = MAX (alignment,
7108 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
7112 /* Calculate the object's offset from the start of the block. */
7113 block = SYMBOL_REF_BLOCK (symbol);
7114 mask = alignment / BITS_PER_UNIT - 1;
7115 offset = (block->size + mask) & ~mask;
7116 SYMBOL_REF_BLOCK_OFFSET (symbol) = offset;
7118 /* Record the block's new alignment and size. */
7119 block->alignment = MAX (block->alignment, alignment);
7120 block->size = offset + size;
7122 vec_safe_push (block->objects, symbol);
7125 /* Return the anchor that should be used to address byte offset OFFSET
7126 from the first object in BLOCK. MODEL is the TLS model used
7127 to access it. */
7130 get_section_anchor (struct object_block *block, HOST_WIDE_INT offset,
7131 enum tls_model model)
7133 char label[100];
7134 unsigned int begin, middle, end;
7135 unsigned HOST_WIDE_INT min_offset, max_offset, range, bias, delta;
7136 rtx anchor;
7138 /* Work out the anchor's offset. Use an offset of 0 for the first
7139 anchor so that we don't pessimize the case where we take the address
7140 of a variable at the beginning of the block. This is particularly
7141 useful when a block has only one variable assigned to it.
7143 We try to place anchors RANGE bytes apart, so there can then be
7144 anchors at +/-RANGE, +/-2 * RANGE, and so on, up to the limits of
7145 a ptr_mode offset. With some target settings, the lowest such
7146 anchor might be out of range for the lowest ptr_mode offset;
7147 likewise the highest anchor for the highest offset. Use anchors
7148 at the extreme ends of the ptr_mode range in such cases.
7150 All arithmetic uses unsigned integers in order to avoid
7151 signed overflow. */
7152 max_offset = (unsigned HOST_WIDE_INT) targetm.max_anchor_offset;
7153 min_offset = (unsigned HOST_WIDE_INT) targetm.min_anchor_offset;
7154 range = max_offset - min_offset + 1;
7155 if (range == 0)
7156 offset = 0;
7157 else
7159 bias = 1 << (GET_MODE_BITSIZE (ptr_mode) - 1);
7160 if (offset < 0)
7162 delta = -(unsigned HOST_WIDE_INT) offset + max_offset;
7163 delta -= delta % range;
7164 if (delta > bias)
7165 delta = bias;
7166 offset = (HOST_WIDE_INT) (-delta);
7168 else
7170 delta = (unsigned HOST_WIDE_INT) offset - min_offset;
7171 delta -= delta % range;
7172 if (delta > bias - 1)
7173 delta = bias - 1;
7174 offset = (HOST_WIDE_INT) delta;
7178 /* Do a binary search to see if there's already an anchor we can use.
7179 Set BEGIN to the new anchor's index if not. */
7180 begin = 0;
7181 end = vec_safe_length (block->anchors);
7182 while (begin != end)
7184 middle = (end + begin) / 2;
7185 anchor = (*block->anchors)[middle];
7186 if (SYMBOL_REF_BLOCK_OFFSET (anchor) > offset)
7187 end = middle;
7188 else if (SYMBOL_REF_BLOCK_OFFSET (anchor) < offset)
7189 begin = middle + 1;
7190 else if (SYMBOL_REF_TLS_MODEL (anchor) > model)
7191 end = middle;
7192 else if (SYMBOL_REF_TLS_MODEL (anchor) < model)
7193 begin = middle + 1;
7194 else
7195 return anchor;
7198 /* Create a new anchor with a unique label. */
7199 ASM_GENERATE_INTERNAL_LABEL (label, "LANCHOR", anchor_labelno++);
7200 anchor = create_block_symbol (ggc_strdup (label), block, offset);
7201 SYMBOL_REF_FLAGS (anchor) |= SYMBOL_FLAG_LOCAL | SYMBOL_FLAG_ANCHOR;
7202 SYMBOL_REF_FLAGS (anchor) |= model << SYMBOL_FLAG_TLS_SHIFT;
7204 /* Insert it at index BEGIN. */
7205 vec_safe_insert (block->anchors, begin, anchor);
7206 return anchor;
7209 /* Output the objects in BLOCK. */
7211 static void
7212 output_object_block (struct object_block *block)
7214 struct constant_descriptor_rtx *desc;
7215 unsigned int i;
7216 HOST_WIDE_INT offset;
7217 tree decl;
7218 rtx symbol;
7220 if (!block->objects)
7221 return;
7223 /* Switch to the section and make sure that the first byte is
7224 suitably aligned. */
7225 switch_to_section (block->sect);
7226 assemble_align (block->alignment);
7228 /* Define the values of all anchors relative to the current section
7229 position. */
7230 FOR_EACH_VEC_SAFE_ELT (block->anchors, i, symbol)
7231 targetm.asm_out.output_anchor (symbol);
7233 /* Output the objects themselves. */
7234 offset = 0;
7235 FOR_EACH_VEC_ELT (*block->objects, i, symbol)
7237 /* Move to the object's offset, padding with zeros if necessary. */
7238 assemble_zeros (SYMBOL_REF_BLOCK_OFFSET (symbol) - offset);
7239 offset = SYMBOL_REF_BLOCK_OFFSET (symbol);
7240 if (CONSTANT_POOL_ADDRESS_P (symbol))
7242 desc = SYMBOL_REF_CONSTANT (symbol);
7243 output_constant_pool_1 (desc, 1);
7244 offset += GET_MODE_SIZE (desc->mode);
7246 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7248 HOST_WIDE_INT size;
7249 decl = SYMBOL_REF_DECL (symbol);
7250 assemble_constant_contents (DECL_INITIAL (decl), XSTR (symbol, 0),
7251 DECL_ALIGN (decl));
7252 size = get_constant_size (DECL_INITIAL (decl));
7253 offset += size;
7254 if ((flag_sanitize & SANITIZE_ADDRESS)
7255 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
7256 && asan_protect_global (DECL_INITIAL (decl)))
7258 size = asan_red_zone_size (size);
7259 assemble_zeros (size);
7260 offset += size;
7263 else
7265 HOST_WIDE_INT size;
7266 decl = SYMBOL_REF_DECL (symbol);
7267 assemble_variable_contents (decl, XSTR (symbol, 0), false);
7268 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
7269 offset += size;
7270 if ((flag_sanitize & SANITIZE_ADDRESS)
7271 && asan_protect_global (decl))
7273 size = asan_red_zone_size (size);
7274 assemble_zeros (size);
7275 offset += size;
7281 /* A htab_traverse callback used to call output_object_block for
7282 each member of object_block_htab. */
7284 static int
7285 output_object_block_htab (void **slot, void *data ATTRIBUTE_UNUSED)
7287 output_object_block ((struct object_block *) (*slot));
7288 return 1;
7291 /* Output the definitions of all object_blocks. */
7293 void
7294 output_object_blocks (void)
7296 htab_traverse (object_block_htab, output_object_block_htab, NULL);
7299 /* This function provides a possible implementation of the
7300 TARGET_ASM_RECORD_GCC_SWITCHES target hook for ELF targets. When triggered
7301 by -frecord-gcc-switches it creates a new mergeable, string section in the
7302 assembler output file called TARGET_ASM_RECORD_GCC_SWITCHES_SECTION which
7303 contains the switches in ASCII format.
7305 FIXME: This code does not correctly handle double quote characters
7306 that appear inside strings, (it strips them rather than preserving them).
7307 FIXME: ASM_OUTPUT_ASCII, as defined in config/elfos.h will not emit NUL
7308 characters - instead it treats them as sub-string separators. Since
7309 we want to emit NUL strings terminators into the object file we have to use
7310 ASM_OUTPUT_SKIP. */
7313 elf_record_gcc_switches (print_switch_type type, const char * name)
7315 switch (type)
7317 case SWITCH_TYPE_PASSED:
7318 ASM_OUTPUT_ASCII (asm_out_file, name, strlen (name));
7319 ASM_OUTPUT_SKIP (asm_out_file, (unsigned HOST_WIDE_INT) 1);
7320 break;
7322 case SWITCH_TYPE_DESCRIPTIVE:
7323 if (name == NULL)
7325 /* Distinguish between invocations where name is NULL. */
7326 static bool started = false;
7328 if (!started)
7330 section * sec;
7332 sec = get_section (targetm.asm_out.record_gcc_switches_section,
7333 SECTION_DEBUG
7334 | SECTION_MERGE
7335 | SECTION_STRINGS
7336 | (SECTION_ENTSIZE & 1),
7337 NULL);
7338 switch_to_section (sec);
7339 started = true;
7343 default:
7344 break;
7347 /* The return value is currently ignored by the caller, but must be 0.
7348 For -fverbose-asm the return value would be the number of characters
7349 emitted into the assembler file. */
7350 return 0;
7353 /* Emit text to declare externally defined symbols. It is needed to
7354 properly support non-default visibility. */
7355 void
7356 default_elf_asm_output_external (FILE *file ATTRIBUTE_UNUSED,
7357 tree decl,
7358 const char *name ATTRIBUTE_UNUSED)
7360 /* We output the name if and only if TREE_SYMBOL_REFERENCED is
7361 set in order to avoid putting out names that are never really
7362 used. */
7363 if (TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl))
7364 && targetm.binds_local_p (decl))
7365 maybe_assemble_visibility (decl);
7368 /* The default hook for TARGET_ASM_OUTPUT_SOURCE_FILENAME. */
7370 void
7371 default_asm_output_source_filename (FILE *file, const char *name)
7373 #ifdef ASM_OUTPUT_SOURCE_FILENAME
7374 ASM_OUTPUT_SOURCE_FILENAME (file, name);
7375 #else
7376 fprintf (file, "\t.file\t");
7377 output_quoted_string (file, name);
7378 putc ('\n', file);
7379 #endif
7382 /* Output a file name in the form wanted by System V. */
7384 void
7385 output_file_directive (FILE *asm_file, const char *input_name)
7387 int len;
7388 const char *na;
7390 if (input_name == NULL)
7391 input_name = "<stdin>";
7392 else
7393 input_name = remap_debug_filename (input_name);
7395 len = strlen (input_name);
7396 na = input_name + len;
7398 /* NA gets INPUT_NAME sans directory names. */
7399 while (na > input_name)
7401 if (IS_DIR_SEPARATOR (na[-1]))
7402 break;
7403 na--;
7406 targetm.asm_out.output_source_filename (asm_file, na);
7409 /* Create a DEBUG_EXPR_DECL / DEBUG_EXPR pair from RTL expression
7410 EXP. */
7412 make_debug_expr_from_rtl (const_rtx exp)
7414 tree ddecl = make_node (DEBUG_EXPR_DECL), type;
7415 enum machine_mode mode = GET_MODE (exp);
7416 rtx dval;
7418 DECL_ARTIFICIAL (ddecl) = 1;
7419 if (REG_P (exp) && REG_EXPR (exp))
7420 type = TREE_TYPE (REG_EXPR (exp));
7421 else if (MEM_P (exp) && MEM_EXPR (exp))
7422 type = TREE_TYPE (MEM_EXPR (exp));
7423 else
7424 type = NULL_TREE;
7425 if (type && TYPE_MODE (type) == mode)
7426 TREE_TYPE (ddecl) = type;
7427 else
7428 TREE_TYPE (ddecl) = lang_hooks.types.type_for_mode (mode, 1);
7429 DECL_MODE (ddecl) = mode;
7430 dval = gen_rtx_DEBUG_EXPR (mode);
7431 DEBUG_EXPR_TREE_DECL (dval) = ddecl;
7432 SET_DECL_RTL (ddecl, dval);
7433 return dval;
7436 #ifdef ELF_ASCII_ESCAPES
7437 /* Default ASM_OUTPUT_LIMITED_STRING for ELF targets. */
7439 void
7440 default_elf_asm_output_limited_string (FILE *f, const char *s)
7442 int escape;
7443 unsigned char c;
7445 fputs (STRING_ASM_OP, f);
7446 putc ('"', f);
7447 while (*s != '\0')
7449 c = *s;
7450 escape = ELF_ASCII_ESCAPES[c];
7451 switch (escape)
7453 case 0:
7454 putc (c, f);
7455 break;
7456 case 1:
7457 /* TODO: Print in hex with fast function, important for -flto. */
7458 fprintf (f, "\\%03o", c);
7459 break;
7460 default:
7461 putc ('\\', f);
7462 putc (escape, f);
7463 break;
7465 s++;
7467 putc ('\"', f);
7468 putc ('\n', f);
7471 /* Default ASM_OUTPUT_ASCII for ELF targets. */
7473 void
7474 default_elf_asm_output_ascii (FILE *f, const char *s, unsigned int len)
7476 const char *limit = s + len;
7477 const char *last_null = NULL;
7478 unsigned bytes_in_chunk = 0;
7479 unsigned char c;
7480 int escape;
7482 for (; s < limit; s++)
7484 const char *p;
7486 if (bytes_in_chunk >= 60)
7488 putc ('\"', f);
7489 putc ('\n', f);
7490 bytes_in_chunk = 0;
7493 if (s > last_null)
7495 for (p = s; p < limit && *p != '\0'; p++)
7496 continue;
7497 last_null = p;
7499 else
7500 p = last_null;
7502 if (p < limit && (p - s) <= (long) ELF_STRING_LIMIT)
7504 if (bytes_in_chunk > 0)
7506 putc ('\"', f);
7507 putc ('\n', f);
7508 bytes_in_chunk = 0;
7511 default_elf_asm_output_limited_string (f, s);
7512 s = p;
7514 else
7516 if (bytes_in_chunk == 0)
7517 fputs (ASCII_DATA_ASM_OP "\"", f);
7519 c = *s;
7520 escape = ELF_ASCII_ESCAPES[c];
7521 switch (escape)
7523 case 0:
7524 putc (c, f);
7525 bytes_in_chunk++;
7526 break;
7527 case 1:
7528 /* TODO: Print in hex with fast function, important for -flto. */
7529 fprintf (f, "\\%03o", c);
7530 bytes_in_chunk += 4;
7531 break;
7532 default:
7533 putc ('\\', f);
7534 putc (escape, f);
7535 bytes_in_chunk += 2;
7536 break;
7542 if (bytes_in_chunk > 0)
7544 putc ('\"', f);
7545 putc ('\n', f);
7548 #endif
7550 static GTY(()) section *elf_init_array_section;
7551 static GTY(()) section *elf_fini_array_section;
7553 static section *
7554 get_elf_initfini_array_priority_section (int priority,
7555 bool constructor_p)
7557 section *sec;
7558 if (priority != DEFAULT_INIT_PRIORITY)
7560 char buf[18];
7561 sprintf (buf, "%s.%.5u",
7562 constructor_p ? ".init_array" : ".fini_array",
7563 priority);
7564 sec = get_section (buf, SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7566 else
7568 if (constructor_p)
7570 if (elf_init_array_section == NULL)
7571 elf_init_array_section
7572 = get_section (".init_array",
7573 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7574 sec = elf_init_array_section;
7576 else
7578 if (elf_fini_array_section == NULL)
7579 elf_fini_array_section
7580 = get_section (".fini_array",
7581 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7582 sec = elf_fini_array_section;
7585 return sec;
7588 /* Use .init_array section for constructors. */
7590 void
7591 default_elf_init_array_asm_out_constructor (rtx symbol, int priority)
7593 section *sec = get_elf_initfini_array_priority_section (priority,
7594 true);
7595 assemble_addr_to_section (symbol, sec);
7598 /* Use .fini_array section for destructors. */
7600 void
7601 default_elf_fini_array_asm_out_destructor (rtx symbol, int priority)
7603 section *sec = get_elf_initfini_array_priority_section (priority,
7604 false);
7605 assemble_addr_to_section (symbol, sec);
7608 /* Default TARGET_ASM_OUTPUT_IDENT hook.
7610 This is a bit of a cheat. The real default is a no-op, but this
7611 hook is the default for all targets with a .ident directive. */
7613 void
7614 default_asm_output_ident_directive (const char *ident_str)
7616 const char *ident_asm_op = "\t.ident\t";
7618 /* If we are still in the front end, do not write out the string
7619 to asm_out_file. Instead, add a fake top-level asm statement.
7620 This allows the front ends to use this hook without actually
7621 writing to asm_out_file, to handle #ident or Pragma Ident. */
7622 if (cgraph_state == CGRAPH_STATE_PARSING)
7624 char *buf = ACONCAT ((ident_asm_op, "\"", ident_str, "\"\n", NULL));
7625 add_asm_node (build_string (strlen (buf), buf));
7627 else
7628 fprintf (asm_out_file, "%s\"%s\"\n", ident_asm_op, ident_str);
7631 #include "gt-varasm.h"